内表面烧结型多孔管的流动沸腾换热

Flow Boiling-based Heat Exchange in an Inner Surface Sintering Type Perforated Tube

采用流动沸腾传热试验平台,研究了2 m长铁基烧结型内表面多孔管竖直管内流动沸腾传热特性,利用流动沸腾传热学基本原理及公式计算了传热过程中的热通量、沸腾传热系数及相关参数,并考察了过热度和流速对多孔管流动沸腾传热性能的影响。结果表明:烧结型表面多孔管的流动沸腾传热能力优于同条件下的光滑管,内表面沸腾传热系数是同尺寸光滑管的1.6倍左右,沸腾所需的壁面过热度比光滑管的低5℃左右,过热度和管内流速增大均可使得多孔管的沸腾传热系数增大。同时分析了表面多孔管比光滑管传热性能优良的原因。

By employing a flow boiling-based heat transfer test platform,studied were the flow boiling-based heat transfer characteristics of an iron-base sintering type perforated vertical tube.By using the basic theory and formula of flow boiling-based heat transfer,the heat flux,boiling heat transfer coefficient and related parameters were calculated and the influence of the superheated degree and flow speed on the flow boiling-based heat transfer performance of the perforated tube was investigated.The research results show that the flow boiling-based heat transfer capacity of the sintering type surface perforated tube is superior to that of a bare tube under the same condition and the inner surface boiling heat transfer coefficient is about 1.6 times of that of a bare tube in the same size.The surface wall superheated degree required for attaining the boiling is about 5 ℃ lower than that of the bare tube.Moreover,to increase the superheated degree and flow speed can both increase the boiling heat transfer coefficient of the perforated tube.In the meantime,the cause that the heat transfer performance of the surface perforated tube is better than that of the bare tube was also analyzed.