Vertical temperature distribution characteristics and adjustment methods of a Trombe wall

摘要

This study proposed a combination of Trombe wall and a photo-thermal collector, in which, the collector was used to prepare hot water and adjust the thermal characteristics of the wall. In the hot climate of Xiangtan (China), the influence of variation in water flow of the collector on the vertical temperature gradient of Trombe wall was studied. Meanwhile, the heat transfer model of the wall system was established and verified using the experimental data. Furthermore, the distribution characteristics of vertical temperature gradient of the wall and the adjustment method were simulated using the heat transfer model. The results show that, under the action of solar irradiance, a large vertical temperature gradient occurred in the Trombe wall. The vertical temperature gradient of the massive wall and the amount of heat transfer through it could be changed by adjusting the water flow and water capacity of the collector. When the water flow was less than 100 L/(h.m(2)), adjusting the water flow had a significant effect on heat transfer temperature difference between the inner and outer surfaces of the wall. Compared with the polyurethane wall, the concrete wall had a smaller vertical temperature gradient, whereas its heat transfer was greater than the polyurethane wall. Additionally, increasing the thickness of the wall could effectively reduce the amount of heat transfer through polyurethane wall, however the effect on reducing the amount of heat transfer through the concrete wall was not obvious.