Thermal comfort evaluation of natural convective-radiant evaporator for air conditioning

The radiant systems come to the fore due to energy saving potential and good integration. The effect of different forms of cold surfaces on human thermal comfort is focused on its application. A novel natural convection-radiant evaporator for heat pumps was developed and its influence on thermal comfort was investigated. A numerical model of the chamber with the evaporator was established and verified with experimental results. Thermal comfort experiments were conducted in a climate chamber and the influence of its asymmetric and uneven cold radiation on the thermal comfort was investigated. Due to the limitation of PMV in uneven radiation situations, the revised predicted mean vote (RPMV) was proposed to assess the thermal comfort in asymmetric and uneven radiation environments based on experimental results. Based on RPMV, the influence of the surface area and temperature of the evaporator on thermal comfort was numerically analyzed. The results indicate that indoor air temperature and relative humidity, RPMV increase with the increase of plate temperature, but decrease with an increase in plate area. The most favourable indoor thermal comfort environment was obtained at an indoor air temperature of 28°C and relative humidity of 50%, which is 2°C higher than traditional air conditioning system.