垂直上升光管内临界压力区水的传热特性研究

对垂直上升光管内临界压力区水的传热特性进行了试验研究。根据试验结果，分别在亚临界部分和超临界部分进行了传热机理分析，得到了垂直上升光管对流沸腾传热随压力，质量流速及热负荷变化的复杂关系，总结了发生传热恶化时的条件，预报了恶化趋势，并给出了能用于工程实际的传热试验关联式。试验结果表明：在亚临界部分中，当压力p/pc为0．98时，发生DNB传热恶化最为明显；在超临界部分中，压力越接近临界压力，传热恶化越剧烈。

Research on the Heat Transfer Performance of Water in Vert ical Upward Smooth Tube under near Critical Pressure

A research on the heat transfer performance of water in vertical upward tube under near critical pressure is presented. It is found that in this region heat transfer characteristics have very complex relationships with pressure, mass velocity and heat flux. Based on the analysis of experimental data, heat transfer equations were obtained within accepted tolerances and could be used in engineering. It is observed that in the subcritical pressure region the heat transfer is most severely impaired at reduced pressure ratio ranging from 0 96 to 0 98, and in the supercritical pressure region heat transfer deterioration is getting worse when pressure approaching to the critical point.