【摘要】 本文提出了一个半圆型垂直沟槽管冷凝传热的物理模型。应用这一模型简化了沟槽内冷凝液的Navier—stokes方程,用有限元法求出了沟槽内冷凝液的流速分布和流量。通过物料和热量衡算得到了流体力学和传热的基本关联式,提出了冷凝给热系数的计算方法。由实验确定膜厚系数n。由以上计算得到管顶到任一位置的平均给热系数和整个管的总平均给热系数。计算结果与实验值吻合较好。在本文条件下,半圆型沟糟管的平均给热系数是光滑管的2.5～6倍.说明半圆型垂直沟糟管在工业生产中是可以使用的。更多还原

【Abstract】 New physical models of condensation heat transfer on semicircle type corrugated surfaces were presented. The numerical solutions to the mathe matical models of hydrodynamic behavier have been made with finite element method, by which the to demensional velocity distribution and the flow vate of condensate have been calculated. Thus the local and average heat transfer coefficients of condensation were obtained. The condensation heat transfer experiments were carried out on semicircle type corrugated surfaces. The comparison of the calculated and experimental results showed that they are agreed well with each other. The theoretical and experimental results also showed that corrugated surfaces offer much higher heat transfer coefficients than the smooth surfaces with steam as working medium.更多还原