Explain an Liquid- vapor Regenerative heat Exchangers
The advantages of suction vapor superheating and liquid sub-cooling can be obtained through a liquid-vapor regenerative heat exchanger. It may be installed in a vapor compression system.
In these heat exchangers, the refrigerant vapor from the evaporator is superheated in a regenerative heat exchanger with consequent sub-cooling of the liquid from the condenser. The effect of this heat exchanger on the thermodynamic vapor compression cycle.
Since the mass flow rate of the liquid and vapor is the same, the heat transfer will be
Heat transfer for superheating = Heat transfer for subcooling
The degree of superheat (t1‘-t1) and the degree of subcooling (t3-t3‘) need not be the same as specific heats of the vapor and liquid phases are different.
The effect of the liquid-vapor regenerative heat exchanger will be;
- Increase in specific volume
- Increase in refrigerating effect.
- Increase in refrigerating capacity.
- Super heating will avoid wet- compression.
- Flashing of the liquid refrigerant in the expansion valve is avoided.
- Optimum compression work is required.