太阳能平板集热器管内流动不均匀性的数值研究

Numerical Investigation of Flow Distribution in Flat Plate Solar Collector

以太阳能平板集热器为研究对象,为了减少管内工质流动的不均匀性,建立了平板集热器管道的物理模型并进行数值研究工作,定量分析了14个支管及2个联箱管道内工质流速的不均匀性。通过改变平板集热器管道的流程及流动方式对管道内工质流速不均匀性进行优化。研究表明:原型及改进后的两种进程方式都存在不均匀性,但改进后能显著降低管道内流速的不均匀性,不同入口流量情况下不均匀度从0.35降低至0.22左右,且C方案的流动不均匀性更稳定。

In order to reduce the non-uniformity of working medium flow in the pipe,a geometric model of solar flat-plate collector is established,and the numerical simulations are performed.The unevenness of flow velocity in 14 branch pipes and 2 header pipes are analyzed quantitatively.The flow and flow mode of the plate collector pipe were changed,the unevenness of the flow velocity of working medium in the pipe was optimized.Results indicate that both the original and the improved modes have non-uniformity,however,the unevenness of flow velocity in the pipeline can be significantly reduced after the improvement.Under different inlet flow conditions,the unevenness decreased from 0.35 to about 0.22,the flow unevenness of scheme C is more stable.