Effect of Control Optimization of CO2 Transcritical Split Air Conditioner on Thermal Comfort of Occupants in Single Zone Room

Abstract

[EN] Energy, environment and economics are considered as very vital parameters for the evaluation of an air conditioning system and associated indoor environment. The cooling performance of an air conditioner has an e®ect on the thermal comfort of occupants in the room. Transcritical CO2 air conditioner (System B) with a control for gas cooler pressure has better energy performance than a transcritical CO2 air conditioner (System A) without any control on the gas cooler pressure. An experimental technique is used for generating performance equations to de¯ne transcritical CO2 air conditioners in the EnergyPlus program. EnergyPlus simulates combined model of a transcritical CO2 air conditioner and room for known yearly weather data for an e®ect on thermal comfort in the room. Thermal comfort in the room is evaluated using the Fanger thermal comfort model and the Pierce two node model. The better energy performance of System B results in improved indoor room environment of the room. The total cooling of System B is 15.78–20.2% higher than that of System A. The Fanger thermal comfort model shows that 95% to 133% people are more dissatis¯ed with an indoor thermal environment during the morning and 85% to 127% people during the afternoon for a room coupled with System A vis-à-vis room with System B.