A multicylinder gasoline engine in an airplane, operating at 2.35 times 103 rev/
ID: 1914387 • Letter: A
Question
A multicylinder gasoline engine in an airplane, operating at 2.35 times 103 rev/min, takes in energy 7 .80 times 103 J and exhausts 4.50 times 103 J for each revolution of the crankshaft. How many liters of fuel does it consume in 1.00 h of operation if the heat of combustion of the fuel is equal to 4.03 times 107 J/L? What is the mechanical power output of the engine? Ignore friction and express the answer in horsepower. What is the torque exerted by the crankshaft on the load? What power must the exhaust and cooling system transfer out of the engine?Explanation / Answer
a)
2.35e3 * 60 * 7.8e3/4.03e7 = 27.29 27.3 L/h
b)
(7.8e3-4.5e3) * 2.35e3 * 0.001341 = 10399 hp
c)
= (7.8e3-4.5e3) * 2.35e3 / (2*3.1416*2.35e3) = 525 N.m
d)
4.5e3 * 2.35e3 = 10575000 W