单选题 For the same Rankine cycle unit, if the steam pressure is increased, its thermal efficiency will ().
A、 Increase slightly, exhaust steam dryness decreases
B、 Remain unchanged, exhaust steam dryness increases
C、 Increase slightly, exhaust steam dryness increases
D、 Both thermal efficiency and dryness remain unchanged
单选题 In the absorption refrigeration cycle, the system consisting of desorber, heat exchanger, absorber and pump is equivalent to () of another type of refrigeration cycle.
A、 Throttle valve
B、 Expansion turbine
C、 Compressor
单选题 Which of the following measures can improve the thermal efficiency of the Rankine cycle?
A、 Reduce the steam superheat temperature under the same steam pressure.
B、 Reduce the steam pressure under other unchanged conditions.
C、 Increase the back pressure.
D、 Adopt the feed water regenerative cycle or steam reheat cycle.
单选题 To improve the thermal efficiency of the steam power cycle, a series of measures can be taken. Which statement is incorrect?
A、 For the same Rankine cycle power unit, increase the steam superheat temperature and steam pressure.
B、 For the same Rankine cycle power unit, increase the exhaust steam pressure.
C、 Improve the Rankine cycle by adopting the reheat cycle.
D、 Improve the Rankine cycle by adopting the regenerative cycle.
单选题 For the same Rankine cycle unit, if the steam superheat degree is increased, its thermal efficiency will ().
A、 Increase slightly, exhaust steam dryness decreases
B、 Remain unchanged, exhaust steam dryness increases
C、 Increase slightly, exhaust steam dryness increases
D、 Both thermal efficiency and dryness remain unchanged
单选题 Which statement about the refrigeration cycle is incorrect?
A、 In winter, the outdoor unit of the air conditioner is the evaporator.
B、 In summer, the indoor unit of the air conditioner is the evaporator.
C、 The cooling capacity required for freezing fish and meat in the refrigerator is provided by the heat absorbed by the condenser.
D、 The cooling capacity required for freezing fish and meat in the refrigerator is provided by the heat absorbed by the evaporator.
单选题 The inversion curve on the throttling effect T-P diagram represents the locus of ().
单选题 The refrigerant of a compression refrigeration unit has a saturation temperature 5℃ lower than that at the original condensation pressure due to the change of cooling medium in the original condenser. The refrigeration cycle will ().
A、 Cooling capacity increases, power consumption remains unchanged
B、 Cooling capacity remains unchanged, power consumption decreases
C、 Cooling capacity decreases, power consumption decreases
D、 Cooling capacity increases, power consumption increases
2026-01-03
共38道
