diesel power plant

DIESEL POWER PLANT

YASHVIR SINGH

contents

• Advantages• Disadvantages• Application of diesel power plant• Components of diesel power plant• Schematic layout of diesel power plant• Selection of site• I C engine terminology• Air standard diesel cycle• Definitions• Heat balance sheet• Common rail system• Fuel nozzles• Objectives of lubrication system• Types of lubrication system• Wet sump lubrication system• Dry sump lubrication system• Supercharging and turbo charging• Cooling system• Water cooling system

Advantages

• They can installed quickly• They can be started and stopped quickly• It does need any warming up period• Cooling water requirements are low• System is more clean and fuel handling system is

comparatively simpler to steam power plant

Disadvantages

• The capacity of diesel power plant is limited compared to steam or hydraulic power plants

• Generation cost per unit is high• These plants are not suitable for continuous over loads• It has high maintenance and lubrication costs• It is noisy in operation

Application of diesel power plants

• Central power station• Peak load plants• Stand by units• Emergency plants• Mobile plants

Components of diesel power plant

• Diesel engine and generator• Engine air intake system• Exhaust system• Cooling system• Engine fuel system• Lubrication system

Schematic layout of diesel power station

Selection of site

• Bearing capacity of the soil• Transport facilities• Located near load centre• Availability of water• Availability of labor

I C Engine terminology

• Bore• Dead centre• Stroke• Clearance volume• Stroke volume• Compression volume• Piston speed

Air standard diesel cycle

Definitions

• Indicated power• Brake power• Mechanical Efficiency• Specific output• Volumetric Efficiency• Thermal efficiency• Relative efficiency• Specific fuel consumption

IP=Pm ALn/60000, (KW)BP=2πNT/60000, (KW)ηm =BP/IPSO=BP/(AXL)Indicated Th. Eff. = IP/(mf X CV)Brake thermal Eff. = BP/(mf X CV)Relative Efficiency= Indicated eff./Air standard eff.Specific fuel consumption, bsfc =(mf /BP)X3600

Heat balance sheet

Heat supplied KJ/min

% Heat expenditure KJ/min

%

Heat supplied by combustion of fuel

- 100 (a) Heat in BP -

(b) Heat rejected to cooling water

-

(c) Heat carried by exhaust

-

(d) Heat unaccounted -

Total - 100 Total - 100

Common rail system

Fuel nozzles

Objectives of lubrication system

• Reduce wear and tear• Provides cooling• Reduction of blow by gases• Reduce vibrations• Cleaning action Reduce friction

Types of lubrication system

• Mist lubrication system• Wet sump(i) Splash lubrication system(ii) Fully pressure feed• Dry sump

Wet sump lubrication system

Dry sump lubrication system

Supercharging and turbocharging

Cooling system

• Air cooling• Water cooling(i) Natural circulation system(ii) Forced circulation system

Water cooling