A flash tank is a common component found in refrigeration systems. A refrigerant enters the flash tank as a wet mixture. The saturated liquid portion of the flow is drawn off at the bottom of the tank and the saturated vapor leaves at the top. Consider the flash tank shown in Figure P3.10. The refrigerant is ammonia and it enters an expansion valve at 10 MPa, 60°C with a flow rate of 12 kg/min and is throttled to a pressure of 100 kPa before it enters an insulated flash tank.
Determine,

a. The temperature of the ammonia entering the flash tank

b. The mass flow rate of the saturated liquid and saturated vapor leaving the tank (kg/min)
Now, consider the case where the flash tank has been in operation for several years and its insulation layer has degenerated causing heat to be transferred to the tank at a rate of 20 kW. Under this condition, determine,

c. The mass flow rate of the saturated liquid and saturated vapor leaving the tank (kg/min)

Transcribed Image Text:

P = 100 kPa. FIGURE P3.10 Ammonia flash tank in a refrigeration system. P = 10 MPa T = 60C m, = 12 kg/min Flash tank 3