Question

Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 22oC and exits at 2.0 bar. The refrigerant undergoes a throttling process. Determine the temperature, in oC, and the quality of the refrigerant at the exit of the expansion valve.

Answer 1

Answer:

The  the quality of the refrigerant at the exit of the expansion valve is 0.179.

Explanation:

Given that,

Initial pressure = 10 bar

Temperature = 22°C

Final pressure = 2.0 bar

We using the value of h

$h = 293.4\ kJ/kg$

The refrigerant during expansion undergoes a throttling process

Therefore, $h_{1}=h_{2}$

We need to calculate the quality of the refrigerant at the exit of the expansion valve

At 2.0 bar,

The property of ammonia

$h_{f}=47.8 kJ/kg$

$h_{g}=1417.7 kJ/kg$

Using formula

$h_{2}=h_{f}+x(h_{g}-h_{f})$

Put the value into the formula

$293.4 =47.8+x(1417.7-47.8)$

$x=\dfrac{293.4-47.8}{1417.7-47.8}$

$x=0.179$

Hence, The  the quality of the refrigerant at the exit of the expansion valve is 0.179.