Study On Heat Transport Process Of Solar Air Collector

Passive solar houses based on Trombe-wall principle have been extensively used in rural homes in northern China. Some novel solar air collectors have been developed in order to suit for existing building reconstruction and urban buildings. But the most researches of this field mainly focus on the thermal efficiency of solar collectors. The fact shows that heating effect is not so good although outlet temperature of collectors is very high.In this study, the heating system with solar air collector which was developed by ourselves is studied. The research was done by means of experiment and simulation. The influence factors and actual effect with these advanced strategies were experimentally analyzed; thermal efficiency and heat supply of air collectors in natural convection mode are predicted; strategies of vent control and heat distribution method are proposaled. The results are beneficial to solar air collector design integrated building. At the same time, the method of design and test of solar air collector was studied, and experiment experiences in thermal efficiency test of solar air collector are gathered in research process.Several constructive conclusions can be obtained as follows: (1) The effect of air diffusion is very important to optimizing heating effect. It can prevent heat short-circuite effectively. (2) From experimental data, the best air mass flow for the solar air collector studied is 0.034kg/s. (3) Variation of incident angle modifier can be ignored if the experiment is done in 11:00-13:00 in continuous 14 days. (4) The relation formulas of air difference between air outlet and air inlet, solar radiation intensity, heat supply and thermal efficiency in natural convection are researched. Heat supply can be predicted with the temperature of air outlet and inlet. (5) Vent control strategie in solar air collectors with or without thermal mass is analyzed. (6) The dampers made in experiment are very effective on preventing reverse thermo-circulation. It is commended that the dampers should be used in Chinese urban home.