COMPUTER SIMULATION AND ENERGY ANALYSIS OF LOW ENERGY OFFICE ROOM THROUGH UTILIZING PHASE CHANGE MATERIAL-COUPLED HEAT EXCHANGER

Heating, Ventilation and Air Conditioning (HVAC) system is widely used within most buildings in the world. This system consumes large amount of energy in altering the air temperature within the premises to reach a desired human comfort level. This creates a big room for introduction of new technology to reduce the energy consumption of HVAC system. Phase Change Material (PCM) is widely viewed as a great potential in storing energy through latent heat energy storage system (LHTES). In this report, the application of PCM flat slabs in heat exchanger to provide free cooling of air to an office room consists of an occupant and a computer is presented. In heat exchanger model, one half of flow path for air flow and another for adjacent PCM slab and encapsulation were simulated. In office room model, a rectangular room model with an occupant and a computer is simulated. The effect of PCM on outlet temperature of PCM-coupled heat exchanger and the thermal comfort of the occupant in an office room model is studied. Energy analysis is performed on total energy saved when substituting conventional HVAC with PCM-coupled heat exchanger. The validated CFD model showed that PCM-coupled heat exchanger provides thermal comfort air temperature of 21℃ to 24℃ for 10.69 hours. The thermal comfort of occupant in room model can be achieved for 8.33 hours. Daily energy saved by substituting conventional HVAC system with PCM-coupled heat exchanger is 5072.37 kJ.