Study on Thermal Environment of Direct Gain Solar and Heating Rooms

The indoor thermal environment usually is measured in the condition of heating or cooling. This paper studies the thermal environment in direct gain solar and heating rooms. The indoor and outdoor temperature and relative humidity, inner surface temperature, human action, and times of opening door per day, are field tested and analyzed. PMV index is used to evaluate thermal environment. The results show that the relative humidity in direct gain solar and heating rooms is too low to comfortable. The curtain from closed to open, the window inner surface temperature decreases 13.9 °C in north orientation room, and decrease 10.3 °C in south orientation room. The indoor air temperature, relative humidity and inner surface temperature at the height of 1.5 m change a little by normal opening door. Thermal environment evaluation proves that in cloudy day, north orientation room is more comfortable than the south orientation room, while in sunny day, their difference of thermal sensation decreases. So we suggest that in order to keep thermal comfort, the curtain should be closed on the condition of no solar energy, the relative humidity should be designed during heating design, and the facing correction factors should be revised, so that the south orientation room is comfort in cloudy day. For energy conservation, the north exterior window should be smaller than the south exterior window.