IC Engine
Engine Terminology:
1.Top Dead Center (TDC): Position of the piston when it stops at the furthest point away from the crankshaft.
– Top because this position is at the top of the engines (not always), and dead because the piston stops at this point.
– When the piston is at TDC, the volume in the cylinder is a minimum called the clearance volume.
2. Bottom Dead Center (BDC): Position of the piston when it stops at the point closest to the crankshaft. The volume of the cylinder is maximum.
3. Stroke: Distance traveled by the piston from one extreme position to the other: TDC to BDC or BDC to TDC.
4. Bore: It is defined as cylinder diameter or piston face diameter; piston face diameter is the same as cylinder diameter( minus small clearance).
5. Swept volume/Displacement volume: Volume displaced by the piston as it travels through one stroke.
– Swept volume is defined as stroke times bore.
– Displacement can be given for one cylinder or entire engine (one cylinder times number of cylinders).
Clearance volume: It is the minimum volume of the cylinder available for the charge (air or an air-fuel mixture) when the piston reaches at its outermost point (top dead center or outer dead center) during the compression stroke of the cycle.
– The minimum volume of the combustion chamber with a piston at TDC.
Compression ratio: The ratio of total volume to clearance volume of the cylinder is the compression ratio of the engine.
– Typically compression ratio for SI engines varies from 8 to 12 and for CI engines it varies from 12 to 24
1.Top Dead Center (TDC): Position of the piston when it stops at the furthest point away from the crankshaft.
– Top because this position is at the top of the engines (not always), and dead because the piston stops at this point.
– When the piston is at TDC, the volume in the cylinder is a minimum called the clearance volume.
2. Bottom Dead Center (BDC): Position of the piston when it stops at the point closest to the crankshaft. The volume of the cylinder is maximum.
3. Stroke: Distance traveled by the piston from one extreme position to the other: TDC to BDC or BDC to TDC.
4. Bore: It is defined as cylinder diameter or piston face diameter; piston face diameter is the same as cylinder diameter( minus small clearance).
5. Swept volume/Displacement volume: Volume displaced by the piston as it travels through one stroke.
– Swept volume is defined as stroke times bore.
– Displacement can be given for one cylinder or entire engine (one cylinder times number of cylinders).
Clearance volume: It is the minimum volume of the cylinder available for the charge (air or an air-fuel mixture) when the piston reaches at its outermost point (top dead center or outer dead center) during the compression stroke of the cycle.
– The minimum volume of the combustion chamber with a piston at TDC.
Compression ratio: The ratio of total volume to clearance volume of the cylinder is the compression ratio of the engine.
– Typically compression ratio for SI engines varies from 8 to 12 and for CI engines it varies from 12 to 24
No comments:
Post a Comment