A hybrid model for dynamic simulation of an air-cooled heat pump system coupled with a PCM storage tank.

In air conditioning systems, the use of thermal energy storage coupled with heat pump is an efficient way for shifting electricity consumption from peak hours. This paper describes a hybrid dynamic model of an air-cooled heat pump coupled with a PCM (Phase Change Material) storage tank. Static models are used for the compressor and expansion valve of the heat pump. The heat exchangers and the storage models are based on a representation of the fluid flows by a cascade of Continuous Stirred Tank Reactors (CSTRs). The switching procedure between different model configurations associated to phase transitions within heat exchangers and PCM storage tank are mathematically performed by matrix operations. Numerical simulation with the Matlab software has been executed, which has shown qualitatively the relevance of the model.