单项选择题
A.fuel spray； the burning of the fuel B.the burned gas mixture； connecting rod C.medium shaft；crankshaft D.the burned gas mixture； piston rod
In a diesel engine, offers the heat energy directly（）； ...
单项选择题In a diesel engine, offers the heat energy directly（）； works as working medium and changes the heat energy to mechanical energy（）
A.the burning of the fuel； medium shaft B.fuel spray； fresh air C.fuel； fuel spray D.the burning of the fuel； the burned gas mixture
A propeller, in order to operate efficiently, must rota...
单项选择题A propeller, in order to operate efficiently, must rotate at a relatively （） speed.
A.high B.low C.fast D.lowly
Why a gearbox is needed in a ship driven by a medium-sp...
单项选择题Why a gearbox is needed in a ship driven by a medium-speed diesel engine?（）
A.To reduce the main engine speed B.To increase the main engine speed C.To govern the main engine speed D.To fix the propeller shaft
