Post on 26-Nov-2014
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