Modeling and verification of heat pump performance for industrial energy conservation

A detailed mathematical simulation of a water-to-water industrial heat pump was developed. A 2kw heat pump employing refrigerant -12 which was locally designed and built was operated in the laboratory. Performance data from the experiment was used to verify the heat pump component and system mathematical models. The four major components of the heat pump cycle, viz., evaporator, condenser, compressor and expansion valve were modeled individually and were coupled together with a system pressure and flow balance. The horizontal evaporator and condenser with tube side water coolant were modeled, employing the NTU-effectiveness techniques with published heat transfer coefficients including change of phase. The reci coefficients including change of phase. The reciprocating compressor was modeled as a thermodynamic process incorporating the effects of clearance, cylinder intake and discharge processes and motor efficiency.