Chapter 10 Engine working conditions and features Section 1 Working conditions &rated powe According to different conditions,working conditions of engine can be roughly divided into three categories 1.1 Constant speed(fixed)working conditions Changes in engine power,but the crankshaft speed is almost unchanged.Such as driven generators,pumps and other engines. 1.2 Fluid resistance (propeller)working conditions Between engine power and speed is certainly a function,a common power function close to three,namely: Pe≈kn3 Such as the propeller driven by marine engine is such a case.Power absorbed by the propeller and propeller speed to the cube is proportional. 1.3 Surface working conditions Engine power and speed is independent of changes in a wide range,and both have no particular relationship.Cars tractors and other land transport vehicles use such engine. 械电子工程学 Automobile and Tractor Northwest A&F University Automobile and Tractor Northwest A&F University Chapter 10 Engine working conditions and features According to different conditions, working conditions of engine can be roughly divided into three categories : 1.1 Constant speed (fixed) working conditions Changes in engine power, but the crankshaft speed is almost unchanged. Such as driven generators, pumps and other engines. 1.2 Fluid resistance (propeller) working conditions Between engine power and speed is certainly a function, a common power function close to three, namely: Pe≈kn3 Such as the propeller driven by marine engine is such a case. Power absorbed by the propeller and propellerspeed to the cube is proportional. 1.3 Surface working conditions Engine power and speed is independent of changes in a wide range, and both have no particular relationship. Cars、tractors and other land transport vehicles use such engine. Section 1 Working conditions &rated power