Study on the air movement character in solar wall system

A mathematical model for simulating airflow in solar channel of the insulated Trombe solar wall system is proposed. It is assumed the glazing is isothermal and the solar heat absorbed by the wall is transferred to  the air in the channel with a constant flux by natural convection. The mass, momentum and energy  conservation equations are discretized and solved using the finite difference control volume method. An experimental study of solar chimney was used to validate the proposed mathematical model. The differences between the predicted results of airflow rate in solar wall and those of measurement data are less than 3.0% when the width of solar wall is 0.2m and wall temperature is lower than 50℃. When the wall is 0.3m wide, theses differences are lower than 5.0% is the wall temperature less than 50℃. Flow and temperature fields are produced and the results are presented in terms of temperature and velocity distribution in various parts of system. The results show that the solar heat gain and channel width are two important parameters affecting the air flow pattern and heat transfer. Further experimental work is needed to refine the model.