Diesel Engine Power Plant
Prepared By: Nimesh Gajjar
Definition
A generating station in which diesel engine is used as the prime mover for the generation of electrical energy is known as diesel power station.
Diesel power plant
Introduction:
Diesel power plants produce power in the range of 2 to 50 MW.
They are used as standby sets for continuity of supply such as hospitals, telephone exchanges, radio stations, cinema theatres and industries.
They are suitable for mobile power generation and widely used in railways and ships.
Generally 2 stroke diesel engine used for power generation.
USES OF DIESEL ENGINES
TODAY, DIESEL ENGINES ARE USED TO PROVIDE POWER IN A VARIETY OF
APPLICATIONS IN MANY INDUSTRIES
THERE ARE SIX MAJOR USES OF DIESEL ENGINES
AGRICULTURE/FARM
TRANSPORTATION
CONSTRUCTION
FORESTRY
MARINE
ELECTRICAL GENERATION PLANTS
Advantages and Disadvantages of DPP Advantages
(a) The design and layout of the plant are quite simple.
(b) It occupies less space as the number and size of the auxiliaries is small.
(c) can be located at any place.
(d) It can be started quickly and it can pickup load in a short time.
(e) There are no standby losses.
(f) It requires less quantity of water for cooling.
(g) The overall cost is much less than that of steam power station of same
capacity.
(h) The thermal efficiency of the plant is higher than that of a steam power station.
(i) It requires less operating staff. Disadvantages
(a) The plant has high running charges as the fuel (diesel) used is costly.
(b) The plant doesn’t work satisfactorily under overload conditions for a longer period.
(c) The plant can only generate small power.
(d) The cost of lubrication is generally high.
(e) The maintenances charges are generally high
Four Stroke Cycle
• Intake / Suction Compression Power / Expansion Exhaust
Fundamental of Diesel Engine
Four stroke cycle theory
Intake strokePiston moving downIntake valve openExhaust valve closed
Four stroke cycle theory
Compression strokePiston moving upIntake valve closedExhaust valve closed
Four stroke cycle theory
Power strokePiston moving downIntake valve closedExhaust valve closed
Four stroke cycle theory
Exhaust strokePiston moving upIntake valve closedExhaust valve open
Four Stroke Cycle Animation
Four-Stroke Cycle Diesel Engine
• The piston travels from one end of the cylinder to the other four times during
each cycle.
• The fuel is ignited at the beginning of the third stroke of each cycle.
• Intake air flows into each cylinder through intake valves in the cylinder head.
• Exhaust gases leave through exhaust valves.
• On the intake stroke, atmospheric pressure pushes air into the cylinder through
the intake valve.
• The exhaust stroke forces burned gases out through the exhaust valve.
• During the compression and power strokes, both valves are closed.
Two-Stroke Cycle Diesel Engine
• They have only two strokes per cycle.
• The fuel is ignited on every other stroke of the piston.
• In the two-stroke diesel engine, air is forced in and exhaust
gases are forced out on a single stroke.
• Usually a blower forces air into the cylinder through intake
ports.
• The incoming air pushes remaining exhaust gases out of the
cylinder through an exhaust valve.
Two Stroke Animation
Difference between 2S and 4S Engine
Advantages & Disadvantagesto a 4-Stroke Cycle Engine
• High torque output• Smooth running• Quieter operation• Lower emissions output• More forgiving to poor
operational practices• Higher horse power
availability• Heavier construction• No Gas/Oil mixing
Advantages: Disadvantages:
Heavy Limited slope operation More moving parts
Advantages & Disadvantagesto a 2-Stroke Cycle Engine
• Low torque output• Erratic running
Characteristic• Noisy• Higher emissions output• Gas/Oil mixing
Advantages: Disadvantages:
Lighter Can be operated in all positions Less moving parts Higher horse power per cc
displacement
2 Stoke Engines part names
Piston
Cylinder
CrankshaftConnectingRod
Still uses a flywheel(not shown)Combustion
chamber
Intake port
Exhaust port
Reed valve
Transfer port
Crankcase
Diesel