【摘要】 对垂直上升的内螺纹管临界压力区内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 ,得到了垂直上升内螺纹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 ,给出了恶化趋势预报 ,并给出了能用于工程实际的传热试验关联式 .结果表明 :虽然在临界压力区内内螺纹管改善传热的特性有所减弱 ,CHF情况有时在过冷区就发生 ,但是与光管相比 ,内螺纹管在临界压力区内仍然能够很好地改善传热 ,降低壁温 .更多还原

【Abstract】 The heat transfer performance of near critical water in a vertical up-flow internally ribbed tube was studied. It was found that heat transfer characteristics is a complicated function of pressure, mass velocity and heat flux. Correlation formula from experimental data was obtained for use in engineering design. Although in the near critical pressure region the effect of swirl on heat transfer is weaker and critical heat flux (CHF) quality is close to that in subcooled region, internally ribbed tube still performs better than smooth tube.更多还原