低温液体核态流动沸腾传热的机理模型

Mechanism model for nucleate boiling flow of cryogenic liquids

对核态沸腾表面上的各种传热机理进行了分析和量化,建立了低温液体核态流动沸腾传热的机理模型,并将该模型纳入双流体模型实现了数值求解,数值预测的结果详细地反映出了壁面上各参数随流动的变化情况。该机理模型的计算结果表明,气泡挣脱后液体与过热壁面间的激冷效应是导致壁面上各参数在OSV处突变的根本原因。

Heat transfer mechanisms involved in nucleate boiling were analyzed and quantified. A mechanism model dealing with parti- tioning heat flux from the wall during boiling flow of cryogenic liquids was proposed. The new model was then incorporated in the two - fluid model and numerical computation of boiling flow of nitrogen in a vertical tube is performed. The numerical results show that the jump of wall temperature at OSV is mainly due to the quenching heat flux.