Reciprocating Engine Operating Principles (Additional Concepts)

Question 1

distance that the piston moves in the cylinder when the crankshaft rotates between the TDC and BDC

Answer 1

stroke

Question 2

distance between the centerline of the crankshaft journal to the centerline of the crank pins

Answer 2

crank throw

Question 3

1 stroke is equal to __ crank throw/s

Answer 3

2

Question 4

internal diameter of the cylinder

Answer 4

bore

Question 5

minimal piston movement around the TDC and BDC

Answer 5

ineffective crank angle

Question 6

the weight of the fuel burnt (lb) for the power produced (BHP) in unit time (hours)

Answer 6

specific fuel consumption (SFC)

Question 7

volume that remains above the piston when the crankshaft is at BDC

Answer 7

total volume

Question 8

volume displaced by the piston in a single stroke

Answer 8

swept volume

Question 9

volume that remains above the piston when the crankshaft is at TDC

Answer 9

clearance volume

Question 10

relationship of swept volume, clearance volume, and total volume

Answer 10

swept volume + clearance volume = total volume

Question 11

ratio of the volume in the cylinder with the piston at the bottom of its stroke, to the volume remaining with the piston at the top of its stroke

Answer 11

compression ratio

Question 12

It represents the volume of air-fuel mixture that the piston moves through each stroke directly influencing the engine’s power output.

Answer 12

piston displacement

Question 13

1 hp to ft-lb/s

Answer 13

550

Question 14

mechanical efficiency is usually ___ to ___%

Answer 14

80 to 85%

Question 15

ratio of work done by the engine to the mechanical equivalent of the heat supplied in the fuel and is usually 25 to 28%

Answer 15

thermal efficiency

Question 16

ratio of the weight of air and fuel induced into the cylinder on the induction stroke to the weight of air and fuel which would fill the cylinder at standard temperatures and pressures, expressed as a percentage; usually 80% for normally aspirated engines

Answer 16

volumetric efficiency