FACTOID # 10: The total number of state executions in 2005 was 60: 19 in Texas and 41 elsewhere. The racial split was 19 Black and 41 White.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Turbocharger" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Turbocharger
Air foil bearing-supported turbocharger
Air foil bearing-supported turbocharger

In internal combustion engines a turbocharger is a turbine-driven, forced-induction compressor powered by the engine's exhaust gas. This is in contrast to a supercharger, which is mechanically driven by the engine's crankshaft via a belt or chain. Image File history File links This is a lossless scalable vector image. ... The word turbo can refer to: A shortening for turbocharger, an internal-combustion engine component. ... Download high resolution version (1024x785, 77 KB)Turbocharger cutaway. ... Download high resolution version (1024x785, 77 KB)Turbocharger cutaway. ... Foil Bearing Foil bearings are a type of hydrodynamic bearing. ... An internal combustion engine is an engine that is powered by the expansion of hot combustion products of fuel directly acting within an engine. ... A Siemens steam turbine with the case opened. ... Forced induction is a term used to describe internal combustion engines that are not naturally aspirated. ... Look up compressor, compression in Wiktionary, the free dictionary. ... A supercharger (or blower ) is a gas compressor that forces more air into the combustion chamber(s) of an internal combustion engine than is achievable with ambient atmospheric pressure (as seen in a naturally-aspirated engine, see forced induction). ...

Contents

Working principle

A turbocharger consists of a turbine and a compressor linked by a shared axle. The turbine inlet receives exhaust gases from the engine causing the turbine wheel to rotate. This rotation drives the compressor, compressing ambient air and delivering it to the air intake manifold of the engine at higher pressure, resulting in a greater amount of the air entering the cylinder. In some instances, compressed air is routed through an intercooler which cools the air before introduction to the intake manifold, as the reduced density of hot air will cause a loss in power gained through turbocharging. A Siemens steam turbine with the case opened. ... Compressor has several meanings: A gas compressor is a mechanical device that takes in a gas and increases its pressure by squeezing a volume of it into a smaller volume. ... For the Australian rock group, see Intercooler (band). ...


The objective of a turbocharger is the same as a supercharger; to improve upon the size-to-output efficiency of an engine by solving one of its cardinal limitations. A naturally aspirated automobile engine uses only the downward stroke of a piston to create an area of low pressure in order to draw air into the cylinder through the intake valves. Because the pressure in the cylinder cannot go below 0 psi (vacuum), and because of the relatively constant pressure of the atmosphere (about 15 psi), there ultimately will be a limit to the pressure difference across the intake valves and thus the amount of airflow entering the combustion chamber. This ability to fill the cylinder with air is its volumetric efficiency. Because the turbocharger increases the pressure at the point where air is entering the cylinder, and the amount of air brought into the cylinder is largely a function of time and pressure difference, more air will be forced in as the inlet manifold pressure increases. The additional air makes it possible to add more fuel (if a turbo is attached without any other engine enhancements it most likely will cause the engine to run lean -- too much air, not enough fuel), increasing the power and torque output of the engine to about 15 to 40 percent, particularly at high engine rotation speeds. A naturally-aspirated engine (NA - aspiration meaning breathing) refers to an internal combustion engine (normally petrol or diesel powered) that is neither turbocharged nor supercharged. ... A combustion chamber is part of an engine in which fuel is burned. ... Volumetric efficiency in internal combustion engine design refers to the efficiency with which the engine can move the charge into and out of the cylinders. ...


Because the pressure in the cylinder must not go too high to avoid pre-ignition and physical damage, the intake pressure must be controlled and this is done by a wastegate, which controls boost by routing some of the exhaust flow, away from the exhaust side turbine. This controls shaft speed and regulates boost pressure in the inlet tract. A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. ...


The application of a compressor to increase pressure at the point of cylinder air intake is often referred to as forced induction. Centrifugal superchargers operate in the same fashion as a turbo; however, the energy to spin the compressor is taken from the rotating output energy of the engine's crankshaft as opposed to normally exhausted gas from the motor. Superchargers and turbochargers use output energy from an engine to achieve a net gain, which must be provided from some of the engine's total output. In the case of superchargers, either directly or from a separate smaller engine, perhaps electrically driven from the main engine's generator. Forced induction is a term used to describe internal combustion engines that are not naturally aspirated. ... Cover of Hot Rod magazine showing Ford Flathead V8 engine with centrifugal supercharger (on top) The centrifugal type supercharger is practically identical in operation to a turbocharger, with the exception that instead of exhaust gases driving an impeller, there is only a compressor housing, and that is driven from the...


History

The turbocharger was invented by Swiss engineer Alfred Büchi. His patent for a turbo charger was applied for use in 1905.[1] Diesel ships and locomotives with turbochargers began appearing in the 1920s. This article is about the fuel. ...


Aviation

One of the first applications of a turbocharger to a non-Diesel engine came when General Electric engineer Sanford Moss attached a turbo to a V12 Liberty aircraft engine. The engine was tested at Pikes Peak in Colorado at 14,000 feet (4,300 m) to demonstrate that it could eliminate the power losses usually experienced in internal combustion engines as a result of reduced air pressure and density at high altitude. GE redirects here. ... Colombo Type 125 Testa Rossa engine in a 1961 Ferrari 250TR Spyder V-12 engine simplified cross-section V12 redirects here. ... General characteristics Layout V-12 Cooling water Cylinders 12 Valve type Displacement 27 litres Rotation rate 1700 rpm Power 400 hp Power (300 kW Weight 383kg The Liberty L-12 was 27 litre water-cooled 45 degree V-12 aircraft engine of 400 horsepower (300 kW). ... This article is about the mountain in Colorado. ... Official language(s) English Demonym Coloradan Capital Denver Largest city Denver Largest metro area Denver-Aurora Metro Area Area  Ranked 8th in the US  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ...


Turbochargers were first used in production aircraft engines in the 1930s before World War II. The primary purpose behind most aircraft-based applications was to increase the altitude at which the airplane can fly, by compensating for the lower atmospheric pressure present at high altitude. Aircraft such as the Lockheed P-38, Boeing B-17 Flying Fortress and Republic P-47 all used exhaust driven "turbo-superchargers" to increase high altitude engine power. It is important to note that the majority of turbosupercharged aircraft engines used both a gear-driven second stage centrifugal type supercharger and a first stage turbocharger. Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... Atmospheric pressure is the pressure at any given point in the Earths atmosphere. ... The Lockheed P-38 Lightning was one of the most important American fighters of the Second World War. ... A B_17 nicknamed Sally B in England in 2001 The B_17 Flying Fortress was the first mass_produced, four_engine heavy bomber. ... The Republic P-47 Thunderbolt, or Jug as it was known, was one of the main US Army Air Force (USAAF) fighters of World War II. The P-47 was a big, rugged, overbuilt aircraft that was effective in air combat but proved particularly useful as a fighter-bomber. ... Cover of Hot Rod magazine showing Ford Flathead V8 engine with centrifugal supercharger (on top) The centrifugal type supercharger is practically identical in operation to a turbocharger, with the exception that instead of exhaust gases driving an impeller, there is only a compressor housing, and that is driven from the...


Automobile

The first Turbo-Diesel truck was produced by the "Schweizer Maschinenfabrik Saurer" (Swiss Machine Works Saurer) 1938 [1]. The turbocharger hit the automobile world in 1952 when Fred Agabashian qualified for pole position at the Indianapolis 500 and led for 100 miles (160 km) before tire shards disabled the blower. Fred Agabashian (21 August 1913 - 13 October 1989) was an American Formula One driver (Indy 500 only) who debuted on May 30, 1950. ... Indy 500 redirects here. ...

The Corvair's innovative turbocharged flat-6 engine. The turbo, located at top right, feeds pressurized air into the engine through the chrome T-tube visible spanning the engine from left to right.
The Corvair's innovative turbocharged flat-6 engine. The turbo, located at top right, feeds pressurized air into the engine through the chrome T-tube visible spanning the engine from left to right.

The first production turbocharged automobile engines came from General Motors in 1962. The A-body Oldsmobile Cutlass Jetfire and Chevrolet Corvair Monza Spyder were both fitted with turbochargers. The Oldsmobile is often recognized as the first, since it came out a few months earlier than the Corvair. Its Turbo Jetfire was a 215 in³ (3.5 L) V8, while the Corvair engine was either a 145 in³ (2.3 L)(1962-63) or a 164 in³ (2.7 L) (1964-66) flat-6. Both of these engines were abandoned within a few years, and GM's next turbo engine came more than ten years later. Image File history File linksMetadata Download high-resolution version (2592x1944, 1243 KB) [edit] Summary [edit] Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Turbocharger Chevrolet Corvair Chevrolet Corvair engine Portal:Cars Portal:Cars/Did you know Metadata... Image File history File linksMetadata Download high-resolution version (2592x1944, 1243 KB) [edit] Summary [edit] Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Turbocharger Chevrolet Corvair Chevrolet Corvair engine Portal:Cars Portal:Cars/Did you know Metadata... Corvair convertible The Chevrolet Corvair was an automobile produced by the Chevrolet division of General Motors from 1960 to 1969. ... The flat-6 engine of the Honda Valkyrie motorcycle A flat-6 is a 6 cylinder configuration of a flat engine or boxer engine. ... The Corvairs innovative flat-6 engine The Chevrolet Corvair engine was a flat-6 piston engine used exclusively in the 1960s Chevrolet Corvair automobile. ... General Motors Corporation (NYSE: GM), also known as GM, is an American automobile maker with worldwide operations and brands including Buick, Cadillac, Chevrolet, GMC, Holden, Hummer, Opel, Pontiac, Saturn, Saab and Vauxhall. ... It has been suggested that this article or section be merged into List of GM platforms. ... The Oldsmobile Cutlass was an automobile made by the Oldsmobile division of General Motors. ... Corvair convertible The Chevrolet Corvair was an automobile produced by the Chevrolet division of General Motors from 1960 to 1969. ... This article does not cite any references or sources. ... The Liberty V8 aircraft engine clearly shows the configuration A V8 engine is a V engine with eight cylinders. ... The Corvairs innovative flat-6 engine The Chevrolet Corvair engine was a flat-6 piston engine used exclusively in the 1960s Chevrolet Corvair automobile. ... The flat-6 engine of the Honda Valkyrie motorcycle A flat-6 is a 6 cylinder configuration of a flat engine or boxer engine. ...


Offenhauser's turbocharged engines returned to Indianapolis in 1966, with victories coming in 1968. The Offy turbo peaked at over 1,000 hp (750 kW) in 1973, while Porsche dominated the Can-Am series with a 1,100 hp (820 kW) 917/30. Turbocharged cars dominated the Le Mans between 1976 and 1988, and then from 2000-2007. Offenhauser was a Formula One engine manufacturer from 1950 through 1960 for the Indianapolis 500. ... This article is about the auto company. ... This article is about the motorsport cup. ... The Porsche 917 gave Porsche its first overall wins at the 24 hours of Le Mans in 1970 and 1971. ... The 24 Hours of Le Mans (24 Heures du Mans) is the worlds most famous sports car endurance race, held annually at Circuit de la Sarthe near Le Mans, France, in the French Sarthe département. ...


BMW led the resurgence of the automobile turbo with the 1973 2002 Turbo, with Porsche following with the 911 Turbo, introduced at the 1974 Paris Motor Show. Buick was the first GM division to bring back the turbo, in the 1978 Buick Regal, followed by the Mercedes-Benz 300SD and Saab 99 in 1978. Japanese manufacturers and Ford followed suit, with Mitsubishi Lancer in 1978, Ford Mustang in 1979, Audi Quattro in 1980, Toyota Supra in 1980, Nissan 280ZX in 1982 and Mazda RX-7 in 1987. For other uses, see BMW (disambiguation). ... See also BMW 2002tii The BMW New Class was a line of compact sedans launched with the 1962 1500. ... Porsche 911 in hillclimb The Porsche 911 (pronounced as nine eleven, neun elfer in German) is a sports car made by Porsche AG of Stuttgart, Germany. ... The Mondial de lAutomobile (Paris Motor Show in English) is an annual auto show in Paris. ... The Buick Regal is a mid-size car produced by General Motors Buick division from 1973 through 2004, during which Buick also used the Century name on mid-size models; the two frequently shared bodies and powertrains. ... This page is about the Mercedes-Benz brand of automobiles and trucks from the DaimlerChrysler automobile manufacturer. ... The 99 was an automobile produced by Saab from 1969 to 1984. ... Japan (Nippon) Japan is the worlds largest automobile manufacturer and exporter, and has six of the worlds ten largest automobile manufacturers. ... Ford may mean a number of things: A ford is a river crossing. ... The Mitsubishi Lancer is a compact car built by Mitsubishi Motors. ... For other Ford Mustang models and concepts, see Ford Mustang Variants. ... This article refers to the car named the Audi Quattro. ... This article is about the automobile. ... The Nissan 280ZX (also known as the Datsun 280ZX) was a sports coupe produced from 1978 to 1983. ... The Mazda RX-7 (also called the Ẽfini RX-7) is a sports car produced by the Japanese automaker Mazda from 1978 to 2002. ...


The world's first production turbodiesel automobile was also introduced in 1978 by Mercedes-Benz with the launch of the 300SD turbodiesel. Today, nearly all automotive diesels are turbocharged. This page is about the Mercedes-Benz brand of automobiles and trucks from the DaimlerChrysler automobile manufacturer. ...


Alfa Romeo introduced the first mass-produced Italian turbocharged car, the Alfetta GTV 2000 Turbodelta in 1979. Pontiac also introduced a turbo in 1980 and Volvo Cars followed in 1981. Maserati in 1980 was the first to introduce twin or bi-turbo Maserati Biturbo. Renault however gave another step and installed a turbocharger to the smallest and lightest car they had, the R5, making it the first Supermini automobile with a turbocharger in year 1980. This gave the car about 160 bhp (120 kW) in street form and up to 300+ in race setup, which was extraordinary output for a 1400 cc motor. The R5's powerful motor was complemented by an incredible lightweight chassis, and as a consequence it was possible for an R5 to nip at the heels of the quick Italian sports car Ferrari 308. Alfa Romeo is an Italian automobile manufacturing company, founded as Darracq Italiana by Cavaliere Ugo Stella, an aristocrat from Milan in partnership with the French automobile firm of Alexandre Darracq. ... This article is about Pontiac automobiles; for the Native American leader, see Chief Pontiac, for other uses see the Pontiac (disambiguation). ... Volvo Cars, or Volvo Personvagnar, is a well-known Swedish automobile maker founded in 1927 in the city of Gothenburg in Sweden. ... This article is about the automobile manufacturer. ... The Maserati Biturbo (IPA: bi. ... For the author, see Mary Renault. ... See also Renault 5 Turbo for the mid-engined sports car The Renault 5 is a sub-compact automobile produced by the French manufacturer Renault. ... 1996 Volkswagen Polo, a popular modern European supermini A supermini is a European hatchback car category. ... This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...


Competition cars

In Formula One, in the so called "Turbo Era" of 1977 until 1989, engines with a capacity of 1500 cc could achieve anywhere from 1000 to 1500 hp (746 to 1119 kW) (Renault, Honda, BMW, Ferrari). Renault was the first manufacturer to apply turbo technology in the F1 field, in 1977. The project's high cost was compensated for by its performance, and led to other engine manufacturers following suit. The Turbo-charged engines took over the F1 field and ended the Ford Cosworth DFV era in the mid 1980s. However, the FIA decided that turbos were making the sport too dangerous and expensive, and from 1987 onwards, the maximum boost pressure was reduced before the technology was banned completely for 1989. F1 redirects here. ... The 1977 Formula One season was the 28th FIA Formula One World Championship season. ... The 1989 Formula One season was the 40th FIA Formula One World Championship season. ... Renault F1 is the Renault companys Formula One racing team. ... Honda Racing F1 Team is a Formula One team run by Japanese car manufacturer Honda. ... For other uses, see BMW (disambiguation). ... This article is about the automobile manufacturer. ... The Cosworth DFV V8 engine (DFV standing for double four valve) was the most successful in the history of Formula 1/Grand Prix motor racing. ... The Fédération Internationale de lAutomobile, commonly referred to as the FIA, is a non-profit association established on June 20, 1904 to represent the interest of motoring organisations and motor car users. ... This article recaps the Formula One season of 1987. ... The 1989 Formula One season was the 40th FIA Formula One World Championship season. ...


In Rallying, turbocharged engines of up to 2000 cc have long been the preferred motive power for the Group A/NWorld Rally Car (top level) competitors, due to the exceptional power-to-weight ratios (and enormous torque) attainable. This combines with the use of vehicles with relatively small bodyshells for manoeuvreability and handling. As turbo outputs rose to similar levels as the F1 category (see above), the FIA, rather than banning the technology, enforced a restricted turbo inlet diameter (currently 34 mm), effectively "starving" the turbo of compressible air and making high boost pressures unfeasible. Petter Solberg driving on gravel at the 2006 Cyprus Rally, a World Rally Championship event. ... WRC is a three-letter abbreviation with multiple meanings, as described below: World Rally Championship, a series of automobile rally races and World Rally Car, the class of cars involved in them Will Rice College, a residential college of Rice University Western Reserve College, a prep school in Hudson, Ohio... The Fédération Internationale de lAutomobile, commonly referred to as the FIA, is a non-profit association established in 1904 to represent the interest of motoring organisations and motor car users. ...


The success of small, turbocharged, four-wheel-drive vehicles in rally competition began with Audi Quattro. In 1981 Audi entered the FIA championship with 4 podium finishes that year, and a manufacturers title in 1982 (2nd and 3rd for driver championship). The advantages of turbochargers combined with all wheel drive were clear, and led to the production of many other similar rally cars including the; Peugeot 205 T16, the Renault 5 Turbo, the Lancia Delta S4 and the Mazda 323GTX, has led to exceptional road cars in the modern era such as the Lancia Delta Integrale, Toyota Celica GT-Four, Subaru Impreza WRX and the Mitsubishi Lancer Evolution. The Jeep Wrangler is a 4WD vehicle with a transfer case to select low range or high range 4WD. The Lamborghini Murciélago is a 4WD/AWD that powers the front via a VCU if the rear slips. ... This article refers to the car named the Audi Quattro. ... The Peugeot 205 is a supermini produced by the French car manufacturer Peugeot between 1983 and 1996. ... The Renault 5 Turbo or R5 Turbo was a high-performance coupé automobile produced by the French manufacturer Renault in the early 1980s. ... The Lancia Delta S4 is a Group B rally car that competed in the World Rally Championship in 1985 and 1986, until Group B cars were banned from competition by the FIA. The car replaced the Lancia 037 Monte Carlo. ... It has been suggested that this article or section be merged into Mazda Familia. ... 1991 Lancia Delta HF Integrale Evoluzione 1989 Lancia Delta HF Integrale Group A 1991 Lancia Delta GT i. ... The Toyota Celica GT-Four is a high performance model of the Celica liftback, with a turbocharged 3S-GTE engine, and full-time 4WD. It was created to compete in the World Rally Championship, whose regulations dictate that a manufacturer must built road-going versions of the vehicle in sufficient... For the high-performance version of the Impreza WRX, see the Subaru Impreza WRX STI The Subaru Impreza WRX, is a turbocharged version of the Subaru Impreza, a two wheel automobile. ... The Mitsubishi Lancer Evolution, colloquially known as the Lancer Evo, is a car manufactured by Mitsubishi Motors. ...


In the late 1970s, Ford and GM looked to the turbocharger to gain power, without sacrificing fuel consumption, during not only the emissions crunch of the federal government but also a gas shortage. GM released turbo versions of the Pontiac Firebird, Buick Regal, and Chevy Monte Carlo. Ford responded with a turbocharged Mustang in the form of the 2.3L from the Pinto. The engine design was dated, but it worked well. The bullet-proof 2.3L Turbo was used in early carburated trim as well as fuel injected and intercooled versions in the Mustang SVO and the Thunderbird Turbo Coupe until 1988. GM also liked the idea enough to evolve the 3.8L V6 used in early turbo Buicks into late '80s muscle in the form of the Buick Grand National and its pinnacle (and final) form, the GNX. It has been suggested that this article or section be merged into Ford Mustang. ... The Ford Thunderbird was a car manufactured in the United States by the Ford Motor Company. ...


Although late to use turbocharging, Chrysler Corporation, after some joint development with Maserati (Chrysler TC), turned to turbochargers in 1984 and quickly churned out more turbocharged engines than any other manufacturer, using turbocharged, fuel-injected 2.2 and 2.5 litre four-cylinder engines in minivans, sedans, convertibles, and coupes. Their 2.2 litre turbocharged engines ranged from 142 hp (106 kW) to 225 hp (168 kW), a substantial gain over the normally aspirated ratings of 86 to 93 horsepower (69 kW); the 2.5 litre engines had about 150 horsepower (110 kW) and had no intercooler. They also pioneered variable geometry turbocharging,(an industry first) with the introduction of the Dodge based 1989 Shelby CSX, a system that completely eliminated "turbo lag".Though the company stopped using turbochargers in 1993,they returned to turbocharged engines in 2002 with their 2.4 litre engines, boosting output by 70 horsepower.[2] For other uses, including the Chrysler Brand, see Chrysler (disambiguation). ... This article is about the automobile manufacturer. ... Chryslers TC by Maserati was a Chrysler K platform GT car jointly developed by Chrysler and Maserati. ... For the Australian rock group, see Intercooler (band). ...


Design details

Components

On the left, the brass oil drain connection. On the right are the braided oil supply line and water coolant line connections.
On the left, the brass oil drain connection. On the right are the braided oil supply line and water coolant line connections.
Compressor impeller side with the cover removed
Compressor impeller side with the cover removed
Turbine side housing removed.
Turbine side housing removed.
A wastegate installed next to the turbocharger.
A wastegate installed next to the turbocharger.

The turbocharger has four main components. The turbine and impeller/compressor wheels are each contained within their own folded conical housing on opposite sides of the third component, the center housing/hub rotating assembly (CHRA). Image File history File linksMetadata Size of this preview: 800 × 300 pixel Image in higher resolution (1600 × 600 pixel, file size: 301 KB, MIME type: image/jpeg) Photo to illustrate connection lines on the CHRA of a turbocharger. ... Image File history File linksMetadata Size of this preview: 800 × 300 pixel Image in higher resolution (1600 × 600 pixel, file size: 301 KB, MIME type: image/jpeg) Photo to illustrate connection lines on the CHRA of a turbocharger. ... Image File history File linksMetadata Size of this preview: 800 × 300 pixel Image in higher resolution (1600 × 600 pixel, file size: 321 KB, MIME type: image/jpeg) Compressor side of a Garrett GT30 turbocharger with the compressor cover removed. ... Image File history File linksMetadata Size of this preview: 800 × 300 pixel Image in higher resolution (1600 × 600 pixel, file size: 321 KB, MIME type: image/jpeg) Compressor side of a Garrett GT30 turbocharger with the compressor cover removed. ... Image File history File linksMetadata Size of this preview: 800 × 300 pixel Image in higher resolution (1600 × 600 pixel, file size: 329 KB, MIME type: image/jpeg) Turbine side of a Garrett GT30 turbocharger with the turbine housing removed. ... Image File history File linksMetadata Size of this preview: 800 × 300 pixel Image in higher resolution (1600 × 600 pixel, file size: 329 KB, MIME type: image/jpeg) Turbine side of a Garrett GT30 turbocharger with the turbine housing removed. ... Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... A Siemens steam turbine with the case opened. ... An impeller is a rotor inside a tube or conduit to increase the pressure and flow of a fluid. ...


The housings fitted around the compressor impeller and turbine collect and direct the gas flow through the wheels as they spin. The size and shape can dictate some performance characteristics of the overall turbocharger. The area of the cone to radius from center hub is expressed as a ratio (AR, A/R, or A:R). Often the same basic turbocharger assembly will be available from the manufacturer with multiple AR choices for the turbine housing and sometimes the compressor cover as well. This allows the designer of the engine system to tailor the compromises between performance, response, and efficiency to application or preference. Both housings resemble snail shells, and thus turbochargers are sometimes referred to in slang as snails. For other uses, see Snail (disambiguation). ... For other uses, see Slang (disambiguation). ...


Split-Inlet Exhaust Housings known as "Twin Scroll" permit the exhaust pulses to be grouped (or separated) by cylinder all the way to the turbine. The reason for doing this in keeping the individual package of energy, an exhaust pulse, intact and undisturbed by other pulses, all the way to the turbine. This in turn can give the turbine a better kick to get it moving. This is specifically useful in four-cylinder engines. Because a four-cylinder only sees one pulse every 180 degrees of crank rotation, it needs all the energy it can get from each pulse. Keeping them separate and undisturbed will therefore pay back some dividends. 5* (Information from "Maximum Boost" by Corky Bell).


The turbine and impeller wheel sizes also dictate the amount of air or exhaust that can be flowed through the system, and the relative efficiency at which they operate. Generally, the larger the turbine wheel and compressor wheel, the larger the flow capacity. Measurements and shapes can vary, as well as curvature and number of blades on the wheels.


The center hub rotating assembly houses the shaft which connects the compressor impeller and turbine. It also must contain a bearing system to suspend the shaft, allowing it to rotate at very high speed with minimal friction. For instance, in automotive applications the CHRA typically uses a thrust bearing or ball bearing lubricated by a constant supply of pressurized engine oil. The CHRA may also be considered "water cooled" by having an entry and exit point for engine coolant to be cycled. Water cooled models allow engine coolant to be used to keep the lubricating oil cooler, avoiding possible oil coking from the extreme heat found in the turbine. Coke Coke is a solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. ...


Boost

Boost refers to the increase in manifold pressure that is generated by the turbocharger in the intake path or specifically intake manifold that exceeds normal atmospheric pressure. This is also the level of boost as shown on a pressure gauge, usually in bar, psi or possibly kPa. This is representative of the extra air pressure that is achieved over what would be achieved without the forced induction. Manifold pressure should not be confused with the volume of air that a turbo can flow. The manifold absolute pressure (MAP) sensor is an important sensor in modern internal combustion engines that use fuel injection. ... An intake is an air intake for an engine. ... In automotive engineering, an intake manifold or inlet manifold is a part of an engine that supplies the fuel/air mixture to the cylinders. ... Atmospheric pressure is the pressure at any given point in the Earths atmosphere. ... Many techniques have been developed for the measurement of reduced or increased pressures. ... The bar (symbol bar), decibar (symbol dbar) and the millibar (symbol mbar, also mb) are units of pressure. ... A pressure gauge reading in PSI (red scale) and kPa (black scale) The pound-force per square inch (symbol: lbf/in²) is a non-SI unit of pressure based on avoirdupois units. ... For other uses, see Pascal. ... Forced induction is a term used to describe internal combustion engines that are not naturally aspirated. ...


Boost pressure is limited to keep the entire engine system, including the turbo, inside its thermal and mechanical design operating range by controlling the wastegate which shunts the exhaust gases away from the exhaust side turbine. A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. ...


The maximum possible boost depends on the fuel's octane rating and the inherent tendency of any particular engine towards preignition. With appropriate calibration and efficient charge cooling, relatively high boost pressures can safely be attained[citation needed]. Ethanol, methanol, liquefied petroleum gas (LPG) and diesel fuels allow higher boost than gasoline, because of these fuels' combustion characteristics. A gas station pump offering five different octane ratings. ... Knocking (also called pinking or pinging)— colloquially detonation—in internal combustion engines occurs when air/fuel mixture in the cylinder detonates or ignites prior to the timed pre-set conditions in the engines cylinder(s). ... Grain alcohol redirects here. ... Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a chemical compound with chemical formula CH3OH (often abbreviated MeOH). ... 45 kg LPG cylinders Liquefied petroleum gas (also called LPG, LP Gas, or autogas) is a mixture of hydrocarbon gases used as a fuel in heating appliances and vehicles, and increasingly replacing chlorofluorocarbons as an aerosol propellant and a refrigerant to reduce damage to the ozone layer. ... This article is about the fuel. ...


Wastegate

By spinning at a relatively high speed the compressor turbine draws in a large volume of air and forces it into the engine. As the turbocharger's output flow volume exceeds the engine's volumetric flow, air pressure in the intake system begins to build. The speed at which the assembly spins is proportional to the pressure of the compressed air and total mass of air flow being moved. Since a turbo can spin to RPMs far beyond what is needed, or of what it is safely capable of, the speed must be controlled. A wastegate is the most common mechanical speed control system, and is often further augmented by an electronic or manual boost controller. The main function of a wastegate is to allow some of the exhaust to bypass the turbine when the set intake pressure is achieved. Most passenger cars have wastegates that are integral to the turbocharger. The manifold absolute pressure (MAP) sensor is an important sensor in modern internal combustion engines that use fuel injection. ... An intake is an air intake for an engine. ... A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. ... A boost controller is a device in a turbocharged or supercharged car that regulates boost pressure. ...


Anti-Surge/Dump/Blow Off Valves

Turbo charged engines operating at wide open throttle and high rpm require a large volume of air to flow between the turbo and the inlet of the engine. When the throttle is closed compressed air will flow to the throttle valve without an exit (i.e. the air has nowhere to go).


This causes a surge which can raise the pressure of the air to a level which can be destructive to the engine (e.g. damage may occur to the throttle plate, induction pipes may burst.) The surge will also decompress back across the turbo as this is the only path that the air can take. This sudden flow of air will often cause turbulence and a subsequent whistling noise as the air moves past the compressor wheel.


The reverse flow back across the turbo acts on the compressor wheel and causes the turbine shaft to reduce in speed quicker than it would naturally. When the throttle is opened again, the turbo will have to make up for lost momentum and will take longer to achieve the required speed, as turbo speed is proportional to boost/volume flow. (This is known as Turbo Lag) In order to prevent this from happening, a valve is fitted between the turbo and inlet which vents off the excess air pressure. These are known as an anti-surge, bypass, blow-off (BOV) or dump valve. They are normally operated by engine vacuum. Dump valves are fitted to the engines of (usually older) turbo charged cars and sit between the turbo outlet and the throttle body. ...


The primary use of this valve is to maintain the turbo spinning at a high speed. The air is usually recycled back into the turbo inlet but can also be vented to the atmosphere. Recycling back into the turbo causes the venting sound to be reduced and is required on an engine that uses a mass-airflow fuel injection system (as opposed to a speed-density system). The reason for this is that the airflow sensor is normally located before the turbo and the ECU will inject enough fuel for the amount of air that flows through it. If some of the air that has gone through the sensor is dumped into the atmosphere, the engine will be over fueled until the BOV closes again. The benefits of venting to the atmosphere are simply the ease of installation (because there is no need to run an extra hose to plumb the charge back into the system) and that it makes a sound considered desirable by some. A dump valve will shorten the time needed to respool the turbo after sudden engine deceleration.


Since a turbocharger increases the specific horsepower output of an engine, the engine will also produce increased amounts of heat. This can sometimes be a problem when fitting a turbocharger to a motor that was not designed to cope with high heat loads. This article is about a unit of measurement. ... For other uses, see Heat (disambiguation) In physics, heat, symbolized by Q, is energy transferred from one body or system to another due to a difference in temperature. ...


It is another form of cooling that has the largest impact on fuel efficiency: charge cooling. Even with the benefits of intercooling, the total compression in the combustion chamber is greater than that in a naturally-aspirated engine. To avoid knock while still extracting maximum power from the engine, it is common practice to introduce extra fuel into the charge for the sole purpose of cooling. While this seems counterintuitive, this fuel is not burned. Instead, it absorbs and carries away heat when it changes phase from liquid mist to gas vapor. Also, because it is more dense than the other inert substance in the combustion chamber, nitrogen, it has a higher specific heat and more heat capacitance. It "holds" this heat until it is released in the exhaust stream, preventing destructive knock. This thermodynamic property allows manufacturers to achieve good power output with common pump fuel at the expense of fuel economy and emissions. The stoichiometric Air-to-Fuel ratio (A/F) for combustion of gasoline is 14.7:1. A common A/F in a turbocharged engine while under full design boost is approximately 12:1. Richer mixtures are sometimes run when the design of the system has flaws in it such as a catalytic converter which has limited endurance of high exhaust temperatures or the engine has a compression ratio that is too high for efficient operation with the fuel given. An engine that requires an overly rich fuel mixture is an indication of a poorly engineered turbo system. For the Australian rock group, see Intercooler_(band). ... A combustion chamber is part of an engine in which fuel is burned. ... A naturally-aspirated engine or normally-aspirated engine (NA - aspiration meaning breathing) refers to an internal combustion engine (normally petrol or diesel powered) that is neither turbocharged nor supercharged. ... Knocking (also called pinking or pinging)—technically detonation— in internal combustion engines occurs when fuel in the cylinder is ignited by the firing of the spark plug but burns too quickly, combusting completely before the optimum moment during the compression phase of the four-stroke cycle. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... Automobile exhaust Exhaust gas is flue gas which occurs as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel, fuel oil or coal. ... Knocking (also called pinking or pinging)—technically detonation— in internal combustion engines occurs when fuel in the cylinder is ignited by the firing of the spark plug but burns too quickly, combusting completely before the optimum moment during the compression phase of the four-stroke cycle. ... In chemistry, stoichiometry is the study of the combination of elements in chemical reactions. ...


Turbochargers also provide more direct fuel savings when compared to a supercharger. The volume, speed and pressure of exhaust gases flowing out of the engine are not only related to engine speed, but also to engine load. An engine under a heavy load has higher internal pressures and temperatures than an engine running under a light load at the same speed. This effect is found on all internal combustion engines, but is especially true for diesel engines. Because the turbocharger is connected to the engine's fuel system, which regulates the supply of fuel in relation to the boost being generated, extra fuel is only delivered when the engine is under load and boost pressures are high. A vehicle with a turbocharged engine travelling at a constant speed on a flat road is placing a relatively small load on its engine- exhaust pressure, boost and fuel delivery is therefore low, and fuel consumption will be close to that of a naturally-aspirated vehicle. The same vehicle maintaining the same speed up a hill will place the engine under a greater load, generating a greater exhaust pressure, raising turbocharger speed, increasing boost pressure and thus causing more fuel to be delivered and more power to be produced. Because boost is related to engine load, the turbocharger only runs at full capacity when the engine is under load. A supercharger, directly geared to the engine, has boost relating solely to engine speed, resulting in higher fuel consumption. Diesel engines in a museum Diesel generator on an oil tanker A diesel engine is an internal combustion engine which operates using the Diesel cycle. ...


Lastly, the efficiency of the turbocharger itself can have an impact on fuel efficiency. Using a small turbocharger will give quick response and low lag at low to mid RPMs, but can choke the engine on the exhaust side and generate huge amounts of pumping-related heat on the intake side as RPMs rise. A large turbocharger will be very efficient at high RPMs, but is not a realistic application for a street driven automobile. Variable vane and ball bearing technologies can make a turbo more efficient across a wider operating range, however, other problems have prevented this technology from appearing in more road cars (see Variable geometry turbocharger). Currently, the Porsche 911 (997) Turbo is the only gasoline car in production with this kind of turbocharger, although in Europe turbos of this type are rapidly becoming standard-fitment on turbodiesel cars, vans and other commercial vehicles, because they can greatly enhance the diesel engine's characteristic low-speed torque. One way to take advantage of the different operating regimes of the two types of supercharger is sequential turbocharging, which uses a small turbocharger at low RPMs and a larger one at high RPMs. The Variable geometry turbocharger (VGT) exists in several forms, usually designed to allow the effective A/R ratio of the turbo to be altered as the conditions change. ... The Porsche Type 997, or simply 997 (nine-nine-seven or nine-ninety-seven) is the project code name for the current version of the sports car Porsche 911, built by the German manufacturer Porsche since 2004. ... For other uses, see Europe (disambiguation). ... Turbodiesel refers to any diesel engine with a turbocharger. ... Diesel engines in a museum Diesel generator on an oil tanker A diesel engine is an internal combustion engine which operates using the Diesel cycle. ... Twin-Turbo, also called bi-turbo by some, refers to a turbocharged engine on which two turbochargers compress the intake charge. ...


The engine management systems of most modern vehicles can control boost and fuel delivery according to charge temperature, fuel quality, and altitude, among other factors. Some systems are more sophisticated and aim to deliver fuel even more precisely based on combustion quality. For example, the Trionic-7 system from Saab Automobile provides immediate feedback on the combustion while it is occurring by using the spark plug to measure the cylinder pressure via the ionization voltage over the spark plug gap. It has been suggested that this article or section be merged with Manifold_absolute_pressure. ... Saab Automobile AB is automobile manufacturing company in Sweden, and is currently a wholly-owned subsidiary of the General Motors Corporation. ...


The new 2.0L TFSI turbo engine from Volkswagen/Audi incorporates lean burn and direct injection technology to conserve fuel under low load conditions. It is a very complex system that involves many moving parts and sensors in order to manage airflow characteristics inside the chamber itself, allowing it to use a stratified charge with excellent atomization. The direct injection also has a tremendous charge cooling effect enabling engines to use higher compression ratios and boost pressures than a typical port-injection turbo engine. Gasoline Direct injection or GDi is a variant of fuel injection employed in modern two- and four- stroke petrol engines. ... VW redirects here. ... Audi AG, more commonly known as Audi, is a premium German automobile manufacturer and one of the worlds leading performance-luxury marques, with headquarters in Ingolstadt, Bavaria. ...


Automotive design details

The ideal gas law states that when all other variables are held constant, if pressure is increased in a system so will temperature. Here exists one of the negative consequences of turbocharging, the increase in the temperature of air entering the engine due to compression. Isotherms of an ideal gas The ideal gas law is the equation of state of a hypothetical ideal gas, first stated by Benoît Paul Émile Clapeyron in 1834. ...


A turbo spins very fast; most peak between 20,000 and 100,000 RPM (using low inertia turbos, 150,000-250,000 RPM) depending on size, weight of the rotating parts, boost pressure developed and compressor design. Such high rotation speeds would cause problems for standard ball bearings leading to failure so most turbo-chargers use fluid bearings. These feature a flowing layer of oil that suspends and cools the moving parts. The oil is usually taken from the engine-oil circuit. Some turbochargers use incredibly precise ball bearings that offer less friction than a fluid bearing but these are also suspended in fluid-dampened cavities. Lower friction means the turbo shaft can be made of lighter materials, reducing so-called turbo lag or boost lag. Some car makers use water cooled turbochargers for added bearing life. This can also account for why many tuners upgrade their standard journal bearing turbos (such as a T25) which use a 270 degree thrust bearing and a brass journal bearing which has only 3 oil passages, to a 360 degree bearing which has a beefier thrust bearing and washer having 6 oil passages to enable better flow, response and cooling efficiency. Turbochargers with foil bearings are in development which eliminates the need for bearing cooling or oil delivery systems, thereby eliminating the most common cause of failure, while also significantly reducing turbo lag. This article is about inertia as it applies to local motion. ... Working principle for a ball bearing. ... Fluid bearings are bearings which solely support the bearings loads on a thin layer of liquid or gas. ... Foil Bearing Foil bearings are a type of hydrodynamic bearing. ...


To manage the upper-deck air pressure, the turbocharger's exhaust gas flow is regulated with a wastegate that bypasses excess exhaust gas entering the turbocharger's turbine. This regulates the rotational speed of the turbine and the output of the compressor. The wastegate is opened and closed by the compressed air from turbo (the upper-deck pressure) and can be raised by using a solenoid to regulate the pressure fed to the wastegate membrane. This solenoid can be controlled by Automatic Performance Control, the engine's electronic control unit or an after market boost control computer. Another method of raising the boost pressure is through the use of check and bleed valves to keep the pressure at the membrane lower than the pressure within the system. A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. ... For other uses, see Solenoid (disambiguation). ... Automatic Performance Control (APC) is a system that was introduced on turbo charged Saab H engines in 1982. ... In automotive electronics, an electronic control unit (ECU) is an embedded microcomputer that controls one or more of the electrical subsystems in a vehicle. ...


Some turbochargers, called Variable-Geometry or Variable-Nozzle turbos, use a set of vanes in the exhaust housing to maintain a constant gas velocity across the turbine, the same kind of control as used on power plant turbines. Other designations for this type of turbo include Variable Area Turbine Nozzle, Variable Turbine Geometry, and Variable Vane Turbine. Such turbochargers have minimal lag like a small conventional turbocharger and can achieve full boost as low as 1,500 engine rpm, yet remain efficient as a large conventional turbocharger at higher engine speeds; they are also used in diesel engines.[3] In many setups these turbos do not use a wastegate[citation needed]; the vanes are controlled by a membrane identical to the one on a wastegate but the mechanism is different[vague]. The Variable geometry turbocharger (VGT) exists in several forms, usually designed to allow the effective A/R ratio of the turbo to be altered as the conditions change. ...


The first production car to use a variable-nozzle turbos was the limited-production 1989 Shelby CSX-VNT equipped with a 2.2L petrol engine[citation needed]. The Shelby CSX-VNT uses a Garrett turbo designated VNT-25, a variable-geometry version of Garrett's T-25. This type of turbine is called a Variable Nozzle Turbine (VNT). A number of other Chrysler Corporation vehicles used this turbocharger in 1990, including the Dodge Daytona and Dodge Shadow. These engines produced 174 horsepower (130 kW) and 225 foot-pounds force (305 N·m) of torque, the same horsepower as the standard intercooled 2.2 liter engines but with 25 more pound-feet of torque and greatly reduced turbo lag. The Shelby CSX was a limited-production performance automobile based on the Dodge Shadow. ... A Petrol engine or Gasoline engine is an internal combustion engine with spark-ignition designed to run on petrol (gasoline) and similar volatile fuels. ... Garrett Engine Boosting Systems is a subsidiary of Honeywell Corporation. ... The Chrysler Corporation was a United States-based automobile manufacturer that existed independently from 1925–1998. ... The Dodge Daytona was a front-wheel drive hatchback based on the Chrysler G platform, which was derived from the Chrysler K platform. ... 1991 Dodge Shadow convertible Pre-facelift Dodge Shadow (5-door) In 1987, the Chrysler Corporation introduced two new compact cars, the Dodge Shadow and the Plymouth Sundance (which turned in similar sales figures), intended to replace the Dodge Charger and Plymouth Turismo, respectively. ...


The 2006 Porsche 911 Turbo has a twin turbocharged 3.6-litre flat six, and the turbos used are BorgWarner's Variable Geometry Turbos (VGTs). This is the third time the technology has been implemented on a production petrol car, after the 1989-90 Chrysler Corporation vehicles and the 1992 Peugeot 405 T16. The Porsche Type 997, or simply 997 (nine-nine-seven or nine-ninety-seven) is the project code name for the current version of the sports car Porsche 911, built by the German manufacturer Porsche since 2004. ... BorgWarner is a U.S. automotive parts supplier, known for its automatic transmissions and turbo chargers. ...


Volkswagen has used Garrett's VNT turbos on the TDI engines of the Mark III and Mark IV series Golf (or Bora) and Jetta (or Vento). The VNT turbos allow the characteristic low-end torque of the diesel engine to be enhanced utilized while also providing extra horsepower often lacking on diesel engines. VW redirects here. ... TDI may stand for: Tabbed document interface, a type of graphical user interface Texas Department of Insurance The Dartmouth Independent, a newspaper at Dartmouth College Time Delay and Integration, timing synchronization in an image sensor Toluene diisocyanate, an organic chemical Turbocharged Direct Injection, a diesel engine used in cars made...


Motorcycles

Using turbochargers to gain performance without a large gain in weight was very appealing to the Japanese factories in the 1980s. The first example of a turbocharged bike is the 1978 Kawasaki Z1R TC. It used a Rayjay ATP turbo kit to build 5 lb (2.3 kg) of boost, bringing power up from ~90 hp to ~105 hp. However, it was only marginally faster than the standard model (11 lb and 145 hp (108 kW) with a modified wastegate). A US Kawasaki importer came up with the idea of modifying the Z1-R with a turbocharging kit as a solution to the Z1-R being a low selling bike. In 1982 Honda released the CX500T featuring a carefully developed turbo (as oppose to the Z1-R's bolt on approach). The development of the CX500T was riddled with problems; due to being a V-twin engine the intake periods in the engine rotation are staggered leading to periods of high intake and long periods of no intake at all. Designing around these problems increased the price of the bike, and the performance still was not as good as the cheaper CX900, making turbocharging motorcycles from factory an educational experience; as of 2007 no factories offer turbocharged motorcycles (although the Suzuki B-King prototype featured a supercharged Hayabusa engine). Kawasaki Heavy Industries, Ltd. ... 1981 Honda CX500 The Honda CX series motorcycles (including the GL500 and GL650 variants) were developed and released in the late 1970s, with production ending in most markets by the mid 1980s. ... Honda 90° transversely mounted V-twin A V-twin is a two cylinder internal combustion engine where the cylinders are arranged in a V configuration. ... 2007 is a common year starting on Monday of the Gregorian calendar. ... For other uses, see Suzuki (disambiguation). ... The Suzuki Hayabusa (also known as the GSX1300R prior to 2008) is a hyper sport motorcycle originally introduced by Suzuki in 1999. ...


Properties and applications

Reliability

Turbochargers can be damaged by dirty or ineffective oil, and most manufacturers recommend more frequent oil changes for turbocharged engines. Many owners and some companies recommend using synthetic oils, which tend to flow more readily when cold and do not break down as quickly as conventional oils. Because the turbocharger will heat when running, many recommend letting the engine idle for one to three minutes before shutting off the engine if the turbocharger was used shortly before stopping (most manufacturers specify a 10-second period of idling before switching off to ensure the turbocharger is running at its idle speed to prevent damage to the bearings when the oil supply is cut off). This lets the turbo rotating assembly cool from the lower exhaust gas temperatures, and ensures that oil is supplied to the turbocharger while the turbine housing and exhaust manifold are still very hot; otherwise coking of the lubricating oil trapped in the unit may occur when the heat soaks into the bearings, causing rapid bearing wear and failure when the car is restarted. Even small particles of burnt oil will accumulate and lead to choking the oil supply and failure. This problem is less pronounced in diesel engines, due to the lower exhaust temperatures and generally slower engine speeds. Mobil 1 synthetic motor oil Synthetic oil is oil consisting of chemical compounds which were not originally present in crude oil (petroleum) but were artificially made (synthesized) from other compounds. ... Coke Coke is a solid carbonaceous material derived from destructive distillation of low-ash, low-sulfur bituminous coal. ... Diesel engines in a museum Diesel generator on an oil tanker A diesel engine is an internal combustion engine which operates using the Diesel cycle. ...


A turbo timer can keep an engine running for a pre-specified period of time, to automatically provide this cool-down period. Oil coking is also eliminated by foil bearings. A more complex and problematic protective barrier against oil coking is the use of watercooled bearing cartridges. The water boils in the cartridge when the engine is shut off and forms a natural recirculation to drain away the heat. Nevertheless, it is not a good idea to shut the engine off while the turbo and manifold are still glowing. A turbo timer is a device designed to keep an automotive engine running for a pre-specified period of time in order to automatically execute the cool-down period required to prevent preature turbo wear and failure. ... Foil Bearing Foil bearings are a type of hydrodynamic bearing. ...


In custom applications utilizing tubular headers rather than cast iron manifolds, the need for a cooldown period is reduced because the lighter headers store much less heat than heavy cast iron manifolds. Cast iron usually refers to grey cast iron, but can mean any of a group of iron-based alloys containing more than 2% carbon (alloys with less carbon are carbon steel by definition). ...


Lag

A pair of turbochargers mounted to an Inline 6 engine (2JZ-GTE from a MkIV Toyota Supra) in a dragster.
A pair of turbochargers mounted to an Inline 6 engine (2JZ-GTE from a MkIV Toyota Supra) in a dragster.

A lag is sometimes felt by the driver of a turbocharged vehicle as a delay between pushing on the accelerator pedal and feeling the turbo kick-in. This is symptomatic of the time taken for the exhaust system driving the turbine to come to high pressure and for the turbine rotor to overcome its rotational inertia and reach the speed necessary to supply boost pressure. The directly-driven compressor in a supercharger does not suffer this problem. (Centrifugal superchargers do not build boost at low RPMs like a positive displacement supercharger will). Conversely on light loads or at low RPM a turbocharger supplies less boost and the engine is less efficient than a supercharged engine. Image File history File linksMetadata Download high resolution version (1024x768, 179 KB) Summary A pair of turbochargers mounted to a Toyota Inline 6 in a dragster. ... Image File history File linksMetadata Download high resolution version (1024x768, 179 KB) Summary A pair of turbochargers mounted to a Toyota Inline 6 in a dragster. ... The straight-6 (also inline 6, I-6, or I6) is an internal combustion engine with six cylinders aligned in a single row. ... The Toyota JZ engine family is a series of inline-6 automobile engines. ... This article is about the automobile. ... Drag racing is a form of auto racing in which cars attempt to complete a fairly short, straight and level course in the shortest amount of time. ... For other uses, see Lag (disambiguation). ... Increasing the mass increases the rotational inertia of an object. ... A supercharger (or blower ) is a gas compressor that forces more air into the combustion chamber(s) of an internal combustion engine than is achievable with ambient atmospheric pressure (as seen in a naturally-aspirated engine, see forced induction). ...


Lag can be reduced by lowering the rotational inertia of the turbine, for example by using lighter parts to allow the spool-up to happen more quickly. Ceramic turbines are a big help in this direction. Unfortunately, their relative fragility limits the maximum boost they can supply. Another way to reduce lag is to change the aspect ratio of the turbine by reducing the diameter and increasing the gas-flow path-length. Increasing the upper-deck air pressure and improving the wastegate response helps but there are cost increases and reliability disadvantages that car manufacturers are not happy about. Lag is also reduced by using a foil bearing rather than a conventional oil bearing. This reduces friction and contributes to faster acceleration of the turbo's rotating assembly. Variable-nozzle turbochargers (discussed above) eliminate lag. The aspect ratio of a two-dimensional shape is the ratio of its longer dimension to its shorter dimension. ... A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. ... Foil Bearing Foil bearings are a type of hydrodynamic bearing. ...


Lag can be reduced with the use of multiple turbochargers. Another common method of equalizing turbo lag is to have the turbine wheel "clipped", or to reduce the surface area of the turbine wheel's rotating blades. By clipping a minute portion off the tip of each blade of the turbine wheel, less restriction is imposed upon the escaping exhaust gases. This imparts less impedance onto the flow of exhaust gases at low RPM, allowing the vehicle to retain more of its low-end torque, but also pushes the effective boost RPM to a slightly higher level. The amount of turbine wheel clipping is highly application-specific. Turbine clipping is measured and specified in degrees. For other senses of this word, see torque (disambiguation). ...


Lag is not to be confused with the boost threshold; however, many publications still make this basic mistake. The boost threshold of a turbo system describes the minimum engine RPM at which there is sufficient exhaust flow to the turbo to allow it to generate significant amounts of boost[citation needed]. Newer turbocharger and engine developments have caused boost thresholds to steadily decline to where day-to-day use feels perfectly natural. Putting your foot down at 1200 engine RPM and having no boost until 2000 engine RPM is an example of boost threshold and not lag. If lag was experienced in this situation, the RPM would either not start to rise for a short period of time after the throttle was increased, or increase slowly for a few seconds and then suddenly build up at a greater rate as the turbo become effective. However, the term lag is used erroneously for boost threshold by many manufacturers themselves.


Electrical boosting ("E-boosting") is a new technology under development; it uses a high speed electrical motor to drive the turbocharger to speed before exhaust gases are available, e.g. from a stop-light. The electric motor is about an inch long.[3]


Race cars often utilize an Anti-Lag System to completely eliminate lag at the cost of reduced turbocharger life. Juuso Pykälistö driving a Peugeot 206 World Rally Car at the 2003 Swedish rally Racing cars redirects here. ... Anti-Lag System, ALS, and sometimes also called a Misfiring System or Bang-Bang, is a system used on mainly turbocharged racing and rally engines to eliminate turbo lag. ...


On modern diesel engines, this problem is virtually eliminated by utilizing a variable geometry turbocharger. Diesel engines in a museum Diesel generator on an oil tanker A diesel engine is an internal combustion engine which operates using the Diesel cycle. ... The Variable geometry turbocharger (VGT) exists in several forms, usually designed to allow the effective A/R ratio of the turbo to be altered as the conditions change. ...


Twin turbochargers

Main article: Twin-turbo

Twin-Turbo, also called bi-turbo by some, refers to a turbocharged engine on which two turbochargers compress the intake charge. ...

Parallel

Some engines, such as V-type engines, utilize two identically-sized but smaller turbos, each fed by a separate set of exhaust streams from the engine. The two smaller turbos produce the same (or more) aggregate amount of boost as a larger single turbo, but since they are smaller they reach their optimal RPM, and thus optimal boost delivery, faster. Such an arrangement of turbos is typically referred to as a parallel twin-turbo system. A V engine is a common configuration for an internal combustion engine. ... Twin-Turbo, also called bi-turbo by some, refers to a turbocharged engine on which two turbochargers compress the intake charge. ...


Sequential

Some car makers combat lag by using two small turbos (such as Nissan, Toyota, Subaru, Maserati, Mazda, and Audi). A typical arrangement for this is to have one turbo active across the entire rev range of the engine and one coming on-line at higher RPM. Early designs would have one turbocharger active up to a certain RPM, after which both turbochargers are active. Below this RPM, both exhaust and air inlet of the secondary turbo are closed. Being individually smaller they do not suffer from excessive lag and having the second turbo operating at a higher RPM range allows it to get to full rotational speed before it is required. Such combinations are referred to as a sequential twin-turbo. Sequential twin-turbos are usually much more complicated than a single or parallel twin-turbo systems because they require what amounts to three sets of pipes-intake and wastegate pipes for the two turbochargers as well as valves to control the direction of the exhaust gases. An example of this is the current BMW E60 5-Series 535d. Another well-known example is the 1993-2002 Mazda RX-7. Many new diesel engines use this technology to not only eliminate lag but also to reduce fuel consumption and reduce emissions. Nissan Motor Co. ... Toyota Motor Corporation ) is a multinational corporation headquartered in Japan, and currently is the worlds largest automaker. ... For other uses, see Subaru (disambiguation). ... This article is about the automobile manufacturer. ... This article or section does not cite any references or sources. ... Audi AG, more commonly known as Audi, is a premium German automobile manufacturer and one of the worlds leading performance-luxury marques, with headquarters in Ingolstadt, Bavaria. ... Twin-Turbo, also called bi-turbo by some, refers to a turbocharged engine on which two turbochargers compress the intake charge. ... The BMW E60 automobile platform is the basis of the 2004-onwards 5-Series automobile, replacing the BMW E39. ... The BMW 5 Series is a mid-size luxury car / executive car manufactured by BMW since 1972. ...


Boost Threshold

Turbochargers start producing boost only above a certain rpm (depending on the size of the turbo) because they are powered by the movement of exhaust gases; without an appropriate exhaust gas velocity, they logically cannot force air into the engine. The point at which the airflow in the exhaust is strong enough to force air into the engine is known as the boost threshold rpm. Engineers have, in some cases, been able to reduce the boost threshold rpm to idle speed to allow for instant response.[citation needed].


Both Lag and Threshold characteristics can be acquired through the use of a compressor map using compressor map and a mathematical equation.


Automotive Applications

Turbocharging is very common on diesel engines in conventional automobiles, in trucks, locomotives, for marine and heavy machinery applications. In fact, for current automotive applications, non-turbocharged diesel engines are becoming increasingly rare. Diesels are particularly suitable for turbocharging for several reasons: Diesel engines in a museum Diesel generator on an oil tanker A diesel engine is an internal combustion engine which operates using the Diesel cycle. ... For other uses, see Truck (disambiguation). ... Great Western Railway No. ...

  • Naturally-aspirated diesels will develop less power than a gasoline engine of the same size, and will weigh significantly more because diesel engines require heavier, stronger components. This gives such engines a poor power-to-weight ratio; turbocharging can dramatically improve this P:W ratio, with large power gains for a very small increase in weight.
  • Diesel engines require more robust construction because they already run at very high compression ratio and at high temperatures so they generally require little additional reinforcement to be able to cope with the addition of the turbocharger. Gasoline engines often require extensive modification for turbocharging.
  • Diesel engines have a narrower band of engine speeds at which they operate, thus making the operating characteristics of the turbocharger over that "rev range" less of a compromise than on a gasoline-powered engine.
  • Diesel engines blow nothing but air into the cylinders during cylinder charging, squirting fuel into the cylinder only after the intake valve has closed and compression is almost complete. The fuel burns at the same rate it is injected so there is no chance of detonation. Gasoline/petrol engines differ from this in that both fuel and air are introduced during the intake cycle and both are compressed during the compression cycle. The higher intake charge temperatures of forced-induction engines reduces the amount of compression that is possible with a gasoline/petrol engine, whereas diesel engines are far less sensitive to this. They are sensitive to high intake temperatures only to the extent that it will increase the exhaust temperature damaging valves and the exhaust side of the turbo.

Today, turbocharging is most commonly used on two types of engines: Gasoline engines in high-performance automobiles and diesel engines in transportation and other industrial equipment. Small cars in particular benefit from this technology, as there is often little room to fit a larger-output (and physically larger) engine. Saab is a leader in production car turbochargers, starting with the 1978 Saab 99; all current Saab models are turbocharged with the exception of the 9-7X. The Porsche 944 utilized a turbo unit in the 944 Turbo (Porsche internal model number 951), to great advantage, bringing its 0-100 km/h (0-60 mph) times very close to its contemporary non-turbo "big brother", the Porsche 928. A naturally-aspirated engine or normally-aspirated engine (NA - aspiration meaning breathing) refers to an internal combustion engine (normally petrol or diesel powered) that is neither turbocharged nor supercharged. ... Power-to-weight ratio is a measure commonly used when comparing various vehicles (or engines), including automobiles, motorcycles and aircraft. ... Bold text The compression ratio is a single number that can be used to predict the performance of any engine (such as an internal-combustion engine or a Stirling Engine). ... Saab Automobile AB is automobile manufacturing company in Sweden, and is currently a wholly-owned subsidiary of the General Motors Corporation. ... The 99 was an automobile produced by Saab from 1969 to 1984. ... Interior of the 2006 Saab 9-7X showing the Saab-style dashboard, cupholder, and ignition key location The Saab 9-7X is a Saab-branded midsize SUV based on General Motors GM GMT platform, which also includes the Chevrolet TrailBlazer (and for this the 9-7X has been given the... The 944 was a sports car built by Porsche from 1982 to 1991. ... The Porsche 928 is a grand tourer automobile made by Porsche AG of Germany from 1978 model year to 1995 model year, during which time it was one of their most expensive offerings. ...


In the 1980s, when turbocharged production cars became common, they gained a reputation for being difficult to handle. The tuned engines fitted to the cars, and the often primitive turbocharger technology meant that power delivery was unpredictable and the engine often suddenly delivered a huge boost in power at certain speeds. Some drivers said this made cars such as the BMW 2002 and the Porsche 911 exciting to drive, requiring high levels of skill. Others said the cars were difficult and often dangerous. As turbocharger technology improved, it became possible to produce turbocharged engines with a smoother, more predictable but just as effective power delivery. See also BMW 2002tii The BMW New Class was a line of compact sedans launched with the 1962 1500. ... Porsche 911 in hillclimb The Porsche 911 (pronounced as nine eleven, neun elfer in German) is a sports car made by Porsche AG of Stuttgart, Germany. ...


Chrysler Corporation was an innovator of turbocharger use in the 1980s. Many of their production vehicles, for example the Chrysler LeBaron, Dodge Daytona, Dodge Shadow/Plymouth Sundance twins, and the Dodge Spirit/Plymouth Acclaim twins were available with turbochargers, and they proved very popular with the public. They are still considered competitive vehicles today, and the experience Chrysler obtained in observing turbochargers in real-world conditions has allowed them to further turbocharger technology with the PT Cruiser Turbo, the Dodge SRT-4 and the Dodge Caliber SRT-4. The Chrysler Corporation was a United States-based automobile manufacturer that existed independently from 1925–1998. ... Chrysler introduced the LeBaron model in 1977 as its lowest priced model, and the name was used on various Chryslers until 1995. ... The Dodge Daytona was a front-wheel drive hatchback based on the Chrysler G platform, which was derived from the Chrysler K platform. ... 1991 Dodge Shadow convertible Pre-facelift Dodge Shadow (5-door) In 1987, the Chrysler Corporation introduced two new compact cars, the Dodge Shadow and the Plymouth Sundance (which turned in similar sales figures), intended to replace the Dodge Charger and Plymouth Turismo, respectively. ... The Plymouth Sundance was a compact car produced from 1986 (as a 1987 model) to 1994. ... 1993-95 Dodge Spirit The Dodge Spirit was introduced in January of 1989 as a mid-size 5/6 passenger sedan. ... The Plymouth Acclaim was a mid-size sedan produced from the 1989 to 1995 model years. ... The Chrysler PT Cruiser is a retro-styled wagon from DaimlerChrysler. ... For the Dodge Caliber SRT-4, see Dodge Caliber SRT-4. ... The Dodge Caliber is a compact car produced by the Dodge division of the Chrysler Group. ...


Aircraft Applications

Turbochargers are used in reciprocating aircraft engines which are designed for high altitude use. As an aircraft climbs in altitude, the density of the air surrounding it decreases. As the density of the air decreases, so does the drag on the airframe and the power of the engine. With this in mind, turbochargers were developed for aircraft to keep the pressure of the air entering the engine equivalent to a normally aspirated engine at sea level. In this case the system is called a turbo-normalizer. Other systems use the turbocharger to boost the engine manifold pressure to much higher than sea level pressures; in the area of 35 to 45 inches of mercury; and this is called turbo-boosting. In either case, an automatic or manually-controlled wastegate is used to vary the turbocharger output according to operating conditions. Pressure is the application of force to a surface, and the concentration of that force in a given area. ... A wastegate is a valve that diverts exhaust gases away from the turbine wheel in a turbocharged engine system. ...


Relationship to Gas Turbine Engines

Prior to World War II, Sir Frank Whittle started his experiments on early turbojet engines. Due to a lack of sufficient materials as well as funding, initial progress was slow. However, turbochargers were used extensively in military aircraft during World War II to enable them to fly very fast at very high altitudes. The demands of the war led to constant advances in turbocharger technology, particularly in the area of materials. This area of study eventually crossed over in to the development of early gas turbine engines. Those early turbine engines were little more than a very large turbocharger with the compressor and turbine connected by a number of combustion chambers. The cross over between the two has been shown in an episode of the TV show Scrapheap Challenge where contestants were able to build a functioning Jet Engine using an ex-automotive turbocharger as a compressor. Sir Frank Whittle (June 1, 1907 - August 9, 1996) was a Royal Air Force officer who invented the jet engine in England while Hans von Ohain was inventing the same in Germany. ... For the transportation company in southern China, see TurboJET. Turbojets are the oldest kind of general purpose jet engines. ... This machine has a single-stage centrifugal compressor and turbine, a recuperator, and foil bearings. ... A combustion chamber is part of an engine in which fuel is burned. ... The logo for Scrapheap Challenge. ...


Consider also, for example, that General Electric manufactured turbochargers for military aircraft and held several patents on their electric turbo controls during the war, then used that expertise to very quickly carve out a dominant share of the gas turbine market which they have held ever since. GE redirects here. ...


Advantages and Disadvantages

Advantages

  • More specific power over naturally aspirated engine. This means a turbocharged engine can achieve more power from same engine volume.
  • Better thermal efficiency over both naturally aspirated and supercharged engine when under full load (i.e. on boost). This is because the excess exhaust heat and pressure, which would normally be wasted, contributes some of the work required to compress the air.
  • Weight/Packaging. Smaller and lighter than alternative forced induction systems and may be more easily fitted in an engine bay.
  • Fuel Economy. Although adding a turbocharger itself does not save fuel, it will allow a vehicle to use a smaller engine while achieving power levels of a much larger engine, while attaining near normal fuel economy while off boost/cruising. This is because without boost, only the normal amount of fuel and air are combusted.

Forced induction is a term used to describe internal combustion engines that are not naturally aspirated. ...

Disadvantages

  • Lack of responsiveness if an incorrectly sized turbocharger is used. If a turbocharger that is too large is used it reduces throttle response as it builds up boost slowly. However, doing this may result in more peak power.
  • Boost threshold. Turbocharger starts producing boost only above a certain rpm due to a lack of exhaust gas volume to overcome inertia of rest of turbo propeller. This results in a rapid and nonlinear rise in torque, and will reduce the usable power band of the engine. The sudden surge of power could overwhelm the tires and result in loss of grip, which could lead to understeer/oversteer, depending on the drivetrain and suspension setup of the vehicle. Lag can be disadvantageous in racing. If throttle is applied in a turn, power may unexpectedly increase when the turbo winds up, which can induce wheelspin.
  • Cost. Turbocharger parts are costly to add to naturally aspirated engines. Heavily modifying OEM turbocharger systems also require extensive upgrades that in most cases requires most (if not all) of the original components to be replaced.
  • Complexity. Further to cost, turbochargers require numerous additional systems if they are not to damage an engine. Even an engine under only light boost requires a system for properly routing (and sometimes cooling) the lubricating oil, turbo-specific exhaust manifold, application specific downpipe, boost regulation, and proper gauges (not intrinsically necessary, but very highly recommended). In addition inter-cooled turbo engines require additional plumbing, while highly tuned turbocharged engines will require extensive upgrades to their lubrication, cooling, and breathing systems; while reinforcing internal engine and transmission parts.

It is proposed that this article be deleted, because of the following concern: Inertia handles this well on its own. ...

See also

Boost gauge on a Ford Focus RS (left) A boost gauge is a pressure gauge that indicates manifold air pressure or turbocharger or supercharger boost pressure in an internal combustion engine. ... Twin-Turbo, also called bi-turbo by some, refers to a turbocharged engine on which two turbochargers compress the intake charge. ... A Twincharger system is a combination of both a turbocharger and a supercharger used together to produce positive manifold pressure (Boost) without the spool time associated with turbochargers (Lag). Twincharging permits high power outputs from small capacity engines by allowing engines of a small displacement to operate at a higher... A supercharger (or blower ) is a gas compressor that forces more air into the combustion chamber(s) of an internal combustion engine than is achievable with ambient atmospheric pressure (as seen in a naturally-aspirated engine, see forced induction). ...

References

  1. ^ The turbocharger turns 100 years old this week
  2. ^ Chrysler turbocharged engines (Allpar)
  3. ^ a b Parkhurst, Terry. Turbochargers: an interview with Garrett’s Martin Verschoor. Allpar, LLC. Retrieved on 12 December 2006.
  • Don Sherman (February 2006). "Happy 100th Birthday to the Turbocharger". Automobile Magazine. 
  • Andrew Noakes (Friday 18th March 2005). "Audi Quattro". Pistonheads. 
  • Roman Angelovskij (April 2008). "BorgWarner Turbochargers Catalogue". Turbo3K. 
The November 2006 cover of Automobile Magazine. ...

  Results from FactBites:
 
Howstuffworks "How Turbochargers Work" (648 words)
In order to achieve this boost, the turbocharger uses the exhaust flow from the engine to spin a turbine, which in turn spins an air pump.
Where the turbocharger is located in the car.
The typical boost provided by a turbocharger is 6 to 8 pounds per square inch (psi).
Turbocharger - Wikipedia, the free encyclopedia (4474 words)
Turbochargers are a true gas compressor, as the gas (air) is compressed inside of the turbocharger.
Turbochargers are typically 70-85% efficient, at peak efficiency, due to having to heat the air during the compression.
Turbochargers with foil bearings are in development which eliminates the need for bearing cooling or oil delivery systems, thereby eliminating the most common cause of failure, while also significantly reducing turbo lag.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m