輪機(jī)英語船舶輔助機(jī)械單項(xiàng)選擇題每日一練(2019.01.24)

A.Heat is given off from a high temperature region known as a heat sink
B.Heat transfer rate is affected most by the size of the heat sink involved
C.Heat transfer rate is affected most by the temperature difference between the heat source and the heat sink
D.Heat transfer by radiation will occur only by mass motion of a fluid substance

A.in series
B.in parallel
C.either A or B
D.None of the above is tree

A.fill the unit with saltwater
B.fill the unit with de-scaling compound
C.completely drain the unit
D.tightly seal the unit to exclude air

A.It is required that all ships are provided with two independent steering gear systems that is one main and one auxiliary
B.The auxiliary gear could be power operated in passenger ships
C.The auxiliary gear must be of adequate strength and sufficient to steer a ship at navigable speed
D.All moving parts of the steering gear must be guarded against any possible damage

A.refrigerant overcharge
B.overfeeding by the expansion valve
C.a restricted suction strainer
D.due to short cycling of the compressor