Experimental study on indoor environment thermal comfort of VRF air conditioning systems

In order to study and improve the indoor environment thermal comfort of the VRF air conditioning system, experimental studies are conducted in an artificial environment laboratory simulating real household conditions. Using the control variable method, four groups of control experiments are set up under cooling and heating conditions, and the experimental data are analysed based on the indoor environment thermal comfort evaluation index. The results show that the temperature drop rate is mainly affected by the wind speed setting, the outdoor air temperature and the number of running machines, and the setting temperature has little effect on the temperature drop rate. The temperature rise rate is mainly affected by the wind speed setting and the outdoor air temperature, and the setting temperature and the number of running machines have little effect on the temperature rise rate. Under heating conditions, the vertical temperature difference of the room is minimal when the wind velocity is slow, but the average temperature of the activity area is lower than 18 ℃. The vertical temperature difference can be optimized during the shutdown process, however, it will cause the indoor temperature to decrease by 4 ℃. The design and installation of the movable air guide structure meeting the actual use conditions, reasonably increasing the stop temperature point and increasing the air outlet speed can improve the indoor environment thermal comfort of the VRF air conditioning system.