This document discusses turbochargers, which are devices that increase an engine's power and efficiency by forcing extra air into the combustion chamber using the exhaust gases' kinetic energy. Turbochargers provide benefits like more power without increasing engine size, but can cause issues like turbo lag as the turbine spins up. The document covers different types of turbochargers like twin-scroll and variable-geometry models and discusses their applications, performance characteristics, components, sensitivities, maintenance needs, advantages, and disadvantages.

1. Turbochargers
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2. Contents
 Turbochargers
 Applications
 Performance
 Intercooler
 Wastegate
 Turbolag
 Sensivities
 Maintenance verifications
 Types
 Advantages
 Disadvantages
 References
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3. Turbocharger
 A turbocharger is a turbine-driven forced induction device that increases
an engine's efficiency and power by forcing extra air into the combustion
chamber.
 Turbochargers are powered by the kinetic energy of exhaust gases from
the engine.
 It is used in Cars, Heavy Trucks, Aircrafts &
Ships.
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4. Why We Use it
 Engine Performance
 The amount of fuel and air an engine burns.
 Density
 Temperature
 Pressure
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5. Why We Use it
 Power with altitude.
 More power and efficiency without enlarging the power plant.
 Recapture the heat energy normally wasted out (exhaust).
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6. Applications 6

7. Applications 7

8. Applications 8

9. Applications 9

10. Applications 10

11. Performance
1) The turbine wheel
2) The turbine housing
3) Exhaust gas
4) Exhaust outlet area
5) The compressor wheel
6) The compressor housing
7) Forged steel shaft
8) Compressed air
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12. Performance 12

13. Intercooler
 The compressor wheel spins faster at altitude producing a hotter charge to
the cylinders.
 Decreasing adiabatic efficiency.
 Cooled by either air or water
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14. Intercooler
 The unit on top of this Subaru that looks like a radiator is the intercooler,
which cools the air after it has been compressed by the turbocharger.
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15. Boost Control
 The more increase the pressure of the intake air above the local
atmospheric pressure (boost)
 Power
 Over boosting and damages.
 Wastegate
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16. Wastegate
 A wastegate is a valve similar to a door that can open and close.
 It allows all of the exhaust into the turbine, or it can route part of the
exhaust past the turbine to the exhaust system.
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17. Turbolag
 Immediate power boost
 Time
 This results in a feeling of lag when you step on the gas
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18. Turbolag
 The primary contributors to turbocharger lag.
 Inertia
 Friction
 Compressor load
 Reduction of Turbolag
 Decrease Inertia (mainly by reducing their weight).
 Using multiple turbochargers sequentially or in parallel
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19. Sensivities
 Insufficient lubrication
 Foreign object damage
 Extreme temperatures
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20. Insufficient Lubrication
 Turbine and compressor wheels begin to contact their respective housings.
 Damage to bearings.
 Engine Oil should be changed every 25-35 hours in a turbocharged
engine.
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21. Insufficient Lubrication 21

22. Foreign Object Damage
 Bolts, valves, and rocks will break pieces from the blades or “machine”
them down.
 Abrasive matter (sand, dirt) will wear away the underside of the blades.
 Soft material (shop rags) will bend the compressor blades backwards.
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23. Maintenance Verifications
 Does the shaft spin freely?
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24. Maintenance Verifications
 Wheels should not contact housing
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25. Maintenance Verifications
 Use a light source to carefully examine the condition of the leading edges
of the Turbine Wheel blades.
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26. Types of Turbochargers
 Twin-turbochargers
 Twin-scroll turbochargers
 Variable-geometry turbochargers.
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27. Twin-turbochargers
 Twin-turbo or bi-turbo
 Sequence
 Parallel
 In a parallel configuration, both turbochargers are fed one-half of the
engine’s exhaust.
 In a sequential setup one turbocharger runs at low speeds and the second
turns on at a predetermined engine speed or load.
 Smaller turbochargers have less turbo lag than larger ones, so often two
small turbochargers are used instead of one large one.
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28. Twin-turbochargers 28

29. Twin-scroll turbochargers
 Twin-scroll or divided turbochargers
 Two exhaust gas inlets and two nozzles, a smaller sharper angled one for
quick response and a larger less angled one for peak performance.
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30. Variable-geometry turbochargers
 Variable-geometry or variable-nozzle turbochargers use moveable vanes
to adjust the air-flow to the turbine
 The vanes are placed in front of the turbine like a set of slightly
overlapping walls.
 Results in
 Improved fuel efficiency
 Turbocharger lag
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31. Variable-geometry turbochargers 31

32. Advantages
 Significant increase in horsepower.
 Power vs size: smaller engine displacements (to produce much more
power relative to their size).
 Better fuel economy
 Higher efficiency
 Turbocharger does not drain power from the engine.
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33. Disadvantages
 Turbo lag
 Engine Damage
 Excessive Heat
 Warranty Invalidation
 Insurance
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35. References
 http://en.wikipedia.org/wiki/Turbocharger
 http://www.turbos.bwauto.com/products/turbochargerTurbine.aspx
 http://performancetrends.com/Definitions/Turbo.htm
 http://www.marinediesels.info/Turbocharging/turbocharger_principles.htm
 http://www.ehow.com/info_8474735_disadvantages-turbo-charger.html
 http://www.popularmechanics.com/cars/a7200/forget-the-v6-
turbocharged-and-boosted-small-engines-are-the-future/
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