Question

b)
A heat engine is used to drive a heat pump. The
heat transfer from the heat engine and heat pump
are used to heat the water circulating, through the
radiators of a building. The engine has thermal
efficiency of 27% and the coefficient of performance
( COP) for the heat pump is 4. Determine the ratio
of heat transfer to the circulating water to the heat
supplied to the engine.​

Answer 1

Step-by-step explanation:

A heat engine is used to drive a heat pump. The heat transfers from the heat engine and from the heat engine and from the heat pump are used to heat the water circulating through the radiators of building. The efficiency of the heat engine is 27%. And the coefficient of performance of the heat pump is 4.

Answer 2

Answer:

1.81

Step-by-step explanation:

Properties Given

Thermal Efficiency

Coefficient of Perfomance

Let Q1 be heat entering the engine  

Q2 and Q3 be the heat transfer to water

 

Finding the Ratio

(Q2+Q3)/Q1 = k

Thermal Efficiency,η = 0.27; COP =4

W = ηQ1 = 0.27Q1

Q2 = (1-η) Q1 = 0.73 Q1

Q3 = COP x W = 4 x 0.27 x Q1 = 1.08 Q1

K = (0.73 Q1 + 1.08 Q1)/Q1 = 1.81