During the valve overlap period, the exhaust pressure of a turbochargers, four-stroke/cycle diesel engine must be less than the intake manifold pressure to ensure （）
1、Valve overlap is the period during whi
Valve overlap is the period during which （）.Athe inlet valve is openBthe exhaust valve is openCboth valves are closedDboth valves are ope
2、When the wave period and the apparent
When the wave period and the apparent rolling period are the same（）.Asynchronous rolling occursBroll period decreasesCroll period increasesDroll amplitude is dampened
3、During the fuel injection period, fuel
During the fuel injection period, fuel pressure must exceed cylinder gas pressure to （）.Aensure penetration and distribution of the fuel in th...
4、The longer the ignition delay period r
The longer the ignition delay period resulting from improper use of low cetane fuel, the （）Aless fuel will enter the cylinderBhigher the cylinder combustion temperatureCmore complete the fuel combustionDmore rapid the rise in combustion pressure
5、The period at high or low tide during
The period at high or low tide during which there is no change in the height of the water is called the （）.Arange of the tideBplane of the tideCstand of the tideDreversing of the tide
6、The period of valve overlap is when （）
The period of valve overlap is when （）.Athe inlet valve is openBthe exhaust valve is openCboth valves are closeDboth valves are ope