Performance enhancement of unitary and packaged air conditioners with phase change material

Abstract

A novel method of lowering condensing temperature of unitary and packaged air conditioners from 55 0C to around 45 0C is proposed with Phase Change Material (PCM) around the channels of Mini Channel Heat Exchanger (MCHE). Primary components of an air-conditioning system along with MCHE with PCM around its mini channels are modeled in MATLAB. A case study is performed considering the temperature-time profile of three Indian cities, viz. Bhopal, Jaipur, and Hyderabad to estimate the hourly energy consumption and saving in electrical energy input at various timings throughout the day, particularly in peak summer. Simulation results show that on an average there will be 15 to 25% reduction in power consumption with enhanced performance of an air conditioner throughout the year. Melting of PCM in MCHE begins at around 10.00 hours and continue up to around 22.00 hours during peak summer months depending on the geographical region and then onwards solidification begins and the entire PCM solidifies by around 10.00 hours depending on the temperature of air during the night. The maximum quantity of PCM required is estimated to be 375 kg per TR with latent heat of fusion of 201 kJ/kg.