太阳集热墙通道中气流速度场与温度场的协同性探讨

为了有效提高太阳能的热利用率,本文运用对流换热场协同理论对太阳集热墙通道中的气流速度场和温度场进行了研究,探讨了通道内温度梯度的方向和气流速度比(u/v)对场协同角及对流换热贡献率的影响规律。研究得出:太阳集热墙通道中的场协同性主要取决于集热墙板的形状和通道中气流的输运工况,改善集热墙板的形状可形成有益于对流换热的温度梯度方向角(θ);当θ一定时(θ≠0°),随着气流速度比的增加,对换热的贡献亦增加,且θ越大,效果越明显。由此提出了优化太阳集热墙集热板的思路,设计了一种带孔折型集热板的太阳墙系统并进行了实验验证。

Research on Field-synergy of Airflow Temperature and Velocity in Solar Wall Channel

In order to effectively improve the heat utilization of solar energy,with the convection heat transfer field synergy theory,the airflow velocity field and temperature field of the solar wall channel were studied,the impacts of temperature gradient directions within the channel and air flow speed ratio（u /v） on field synergy angle and convection contribution ratio were discussed.It was presented that the field-synergy of solar collector wall depended on the shape of collector plate and flow conditions in the transport channel.Moreover,it was concluded that the improvement of collector plate shape could form the temperature gradient direction angle（θ） to benefit the convection heat transfer.In detail,with a certain θ（θ≠0°）,the convection contribution ratio would be increased when the flow rate was increased,and the greater of θ,the more obvious of the effect.Therefore,the useful idea for the optimization of solar wall plate was provided.In addition,a folded-type plate with hole solar collector wall system was designed and was verified by the experiments.