Q5Basic Mechanical Engineering

Question

Q.5. Define the performance measure of a refrigerator and a heat pump.

Answer 1

Unlike engines (measured by efficiency $η < 1$ ), cooling/heating devices are measured by COP, which can easily exceed 1.0.

C O P_{R e f} = \frac{Desired Cooling Effect (Heat extracted from cold space)}{Net Work Input required}

C O P_{H P} = \frac{Desired Heating Effect (Heat rejected to warm space)}{Net Work Input required}

Mathematically, operating between the same temperature limits, $C O P_{H P} = C O P_{R e f} + 1$ .

Question