A turbocharger is a turbine-driven device that increases an Internal Combustion Engine's Efficiency and Power Output by forcing extra air into the combustion chamber at higher pressure than atmospheric pressure.
2. Turbocharger
A turbocharger is a turbine-driven device that increases an
Internal Combustion Engine's Efficiency and Power
Output by forcing extra air into the combustion chamber
at higher pressure than atmospheric pressure.
3.
4. Applications
They are used in Automobiles
for Better Fuel Efficiency.
Trucks & Buses etc.
6. Applications (Contd.)
Used in stationary power plants for Additional Power/Cylinder
MAN 18V48/60B uses Single stage Axial Turbocharger TCA-77
MAN 18V48/60TS uses Two stage Axial Turbochargers; First
stage TCA-77 and Second stage TCA-88
9. Working / Operation Principle
A normal turbocharges work on the principle of Forced induction
I.C Engine produce exhaust gases
These exhaust gases drives TURBINE which drives
COMPRESSOR
This draws extra air into combustion chamber at higher pressure
than atmospheric pressure resulting better fuel mixing
12. Design of Turbocharger: Metallurgy
Compressor wheels are made from high strength Aluminium alloys
Turbine wheel is made from titanium alloys, stainless steel alloys
Impurities during manufacturing of compressor wheel can weaken
the metal and can cause cracks so special care is required during
fabrication process
This increase/ decrease of RPM creates cyclic loading or curved
blades therefore Blades must be designed to withstand these cyclic
bending loads and loading from compressing air.
14. Design of Turbocharger: Lubricating system
The lubrication system is critical for normal turbocharger
operation
it performs three important functions: lubricating, cooling and
cleaning
Interruptions of oil supply for only a few seconds can cause
disastrous results due to Excessive heat
It is essential that sufficient quantity of oil continually flows
through the turbocharger to provide suspension and
stabilization of the full floating bearing system and to
remove heat
16. Design of Turbocharger: Balancing
Balancing of Turbocharger is critical as usual operating speed of
turbocharger ranges from 80,000-150,000 RPM
If turbocharger is even slightly imbalanced, it creates immense
offset centrifugal force and causes repeated bearing failure or
Shaft failure
Static and Dynamic balancing is done precisely
ISO 1940-1(2003) is used as standard of guidelines for
balancing of rigid rotors
18. Design of Turbocharger: Bearings
The free-floating journal bearings
are usually made either from a
Brass or Bronze alloy
Holes are drilled for lubrication
system which keeps them
suspended during normal
operation
19. Advantages
Better combustion, better fuel efficiency
Reduces Unburned Hydrocarbons and emissions
Significant increase in Power output
Flexibility of Down sizing of Engine for similar power output
20. Challenges
Boost threshold is required for startup of turbine
Turbolag
Difficult to operate/Control: RPM (50,000-150,000); Bypass
valves and wastegate are required
Periodic maintenance is required; Oil requirements
Precise balancing (Static/Dynamic) is required for normal
operation
21. Turbochargers Vs Superchargers
Turbochargers
It is driven by energy of exhaust gases
No Mechanical load on Engine
No instantaneous power due to Tarbolag
Frequent maintenance & Oil change is
required
High adiabatic efficiency
place exhaust back pressure on engines
Superchargers
It is driven by engine itself
Puts Mechanical load on Engine
Instantaneous power
Little maintenance & Oil change is
needed
Low adiabatic efficiency
No back pressure on engine
22. Variants/Future technologies
Twin turbos; These designs have two separate turbochargers
operating in either a sequence or in parallel. This setup
significantly reduces Turbolag
Variable-geometry or variable-nozzle turbochargers use
moveable vanes to adjust the air-flow to the turbine
Hybrid turbocharger is an electric turbocharger consisting of a
high speed turbine-generator and a high speed electric air
compressor
The electrical motors run at speeds of 120,000 rpm and when
used as generator, which drives compressor and stores energy