Consider a simple ideal Rankine cycle with fixed boiler and

Consider a simple ideal Rankine cycle with fixed boiler and condenser pressures. If the stream is superheated to a higher pressure, then The turbine output will decrease The amount of heat rejected will decreased The cycle efficiency will decrease The moisture content at the turbine exit will decrease In a gas refrigeration cycle (reversed Brayton cycle) where heat is rejected to the ambient, the lowest temperature of the cycle can be lower than the ambient temperature only when employing a regenerator True False For the same heat addition (Q_L), heat rejection (Q_H), and compressor work (W_C), the COP of a refrigerator is than that of a heat pump Greater Less Equal to None of the above

Solution

1.8 correct answer is \"a\" part because on superheating the turbine output will increase as turbine as now more pressure to work with. The amount of heat rejected will increase, the cycle efficiency may increase or decrease depending upon the heat input. The moisture content also depends on the exit conditions of the steam which may increase or decrease the moisture content.

1.9 False .... Generally the temperature at the exit of expander is lower than the atmospheric temperature . If the regeneration is added it will decrease the temperature but it is not necessary that we add regeneration.

1.10 for same heat addition and heart rejection, the cop of refrigerator is always less than heat pump