轮机英语单项选择题每日一练(2019.06.06)

单项选择题
Fuel droplets injected into a diesel engine cylinder must have adequate penetration to （）
A.prolong the ignition delay period
B.ensure the beginning of fuel injection
C.thoroughly utilize the air charge
D.allow controlled fuel combustion
单项选择题
According to Regulations, a power driven auxiliary steering gear for a vessel capable of a 12 knot service speed, must be able to meet the rudder movement requirements at which of the minimum vessel speeds listed below?（）
A.6 knots
B.7 knots
C.9 knots
D.12 knots
单项选择题
Which of the following conditions is realized by the turbo-charging of a previously naturally aspirated diesel engine?（）
A.Ignition lag increases
B.Lube oil system pressure increases
C.Brake specific fuel consumption increased
D.Mechanical efficiency increaded
单项选择题
Fresh water is used for the cooling of cylinder jackets and （） of the marine diesel engine.
A.cylinder covers
B.lubricating space
C.crosshead
D.exhaust manifold
单项选择题
Cylinder lubrication oil for low speed main propulsion diesel engines is admitted to each cylinder during （）.
A.the power stroke
B.the compression stroke
C.low load operation only
D.periods of standby