本文建立了含有液膜和汽膜的竖壁凝结物理模型和基于边界层方程组的数学模型，应用相似理论进行了无因次变换，确定了无因次方程的系数及变换函数的形式，并对控制方程组进行了数值求解，推导了考虑液膜对流因素的竖壁膜状凝结局部努谢尔特数的表达式，进而得出了雷诺数范围较宽的竖壁膜状凝结准则的统一表达式。
A physical model which has both liquid and vapor films and a mathematical modelbased on boundary layer equations for the film condensation on vertical wall sare established. Similarity theory is applied to transform the mathematicale quations dimensionless. The forms of the dimensionless transform functionsare determined. Numerical calculation is performed on the equations. Byconsidering the convection effect, the local Nusselt Number formula forvertical film condensation is modified and a universal equation of Condensation Number for steam condensation on vertical surfaces is derived, which can covera broad Renords Number range for both laminar and turbulent flow.
参考文献
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