CONTENTS:- About DEMU(Diesel Electric Multiple Unit) Engine. About Diesel Locomotive Shed Moula-Ali.(Where we done our mini project) DEMU Engine and Its Systems. Basic requirements of Air intake and exhaust system. Block diagram of Air intake and exhaust system in DEMU Engine. Working of Air intake and exhaust system in DEMU Engine. Precautions for good working of Air intake and exhaust system. conclusion.

2. CONTENTS:-
 About DEMU(Diesel Electric Multiple Unit) Engine.
 About Diesel Locomotive Shed Moula-Ali.(Where we done our mini project)
 DEMU Engine and Its Systems.
 Basic requirements of Air intake and exhaust system.
 Block diagram of Air intake and exhaust system in DEMU Engine.
 Working of Air intake and exhaust system in DEMU Engine.
 Precautions for good working of Air intake and exhaust system.
 conclusion

3. Diesel Electric Multiple Unit(DEMU) Engine
 DEMU (Diesel Electric Multiple Unit) has been inducted in Indian railways to
replace the existing slow moving Loco hauled passenger train in non-electrified
mainline sections.
 The high acceleration potential of DEMU makes them suitable to work as fast
passenger transportation services between cities.
 Its power is 1400HP.

4. About Diesel Locomotive Shed Moula-Ali
 Diesel Shed, Moula-Ali was established in 1984 and located at a
distance of 7 Km from Rail Nilayam, Secunderabad for the maintenance of
diesel locos.
 The shed is also holding 10 DEMUs maintenance meeting the demand of sub-
urban traffic.

5. DEMU Engine and Its Systems
 The various main systems of DEMU are described in this section. The various
systems of DEMU engines are as follow :-
Air Intake and Exhaust system
Fuel system
Lube oil system
Cooling water system
Hydraulic oil system

6. .
Basic requirements of Air intake and exhaust system
 Maximum air should be collected.
 Maximum obstacles should be avoided.
 Air should be filtered as much as it can.
 The required amount of air should be supplied to the fuel which favours the
process.
 The exhaust air should be released into the atmosphere only after removal of
harmful gasses or conversion of harmful gasses which effect the environment
in to less toxic gasses.

7. Block diagram of Air intake and exhaust system in
DEMU Engine.

8. Air intake and exhaust system working
 The main steps involved in Air intake and exhaust system are
1. The atmospheric air is collected from the atmosphere through the air mesh.
2. Then the atmospheric air is passed through the air filter.
3. The air filter is provided to remove harmful dust, abrasive particles from the
air.
4. The filtered air then passes through the turbo supercharger which
compresses and feeds the compressed air to the cylinders via an after cooler
which cools the air.
5. The cooled air is then sent to the engine cylinder which helps in the
combustion of fuel.

9.  The exhaust air from the cylinder drives the turbine portion of the turbo super
charger, which helps in utilisation of residual heat of exhaust gases.
 The exhaust gases are exhausted through a silencer kept on the dished rooftop
of the DEMU.

10. Turbo charger:
 A turbocharger, or turbo, is a gas compressor. It is used to force air into an
internal combustion engine.

12. Precautions for good working of Air intake and exhaust
system
 Oil/lubrication should be done regularly.
 Air filters should be changed or cleaned regularly.
 Ensure air-tight fit on all connections and ducts.
SOME NOTATIONS USED IN RAILWAY LOCOS
*WDG
*WDP
*WDM

13. Conclusion
 A perfect Air intake and exhaust system helps the engine for achieving better
efficiency.
 Use of sensors in air filters helps in finding the amount of dust deposited and
indicates us whether to change the filters or not.
 The Air intake and exhaust system should be in such a way that required
amount of air should be supplied to the fuel which favours the process.