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本文的任务是把上一篇论文的理论引伸到凝结液膜部分湍流条件下的膜状凝结放热.在这个范围里理论分析和实验结果符合的程度达到和层流范围内努谢尔特理论公式和实验结果符合程度相比拟的地步.根据理论分析的结果设计计算的推荐式可采用:Re=0.025((Ga~(1/3)/(Pr·K))~(1.41)这个推荐式给出的放热系数较纯理论式的结果高36%而与实验结果基本一致,同时亦和多种来源的经验公式相近.本文亦给出适用于极低 Pr 数介质凝结液情况的较一般的理论分析.分析的结果指明,对 Pr《1而部分湍流的情况来说,忽略液膜加速度和液膜本身对流所引起的误差较层流时更大。把这个因素考虑在内则此时放热系数的值比努谢尔特公式给出的值更低得多.文章包括了以图表形式表出的最终结果.
The task of this paper is to extend the theory of the previous paper to the film-like condensation exotherm under the turbulent flow conditions of the condensate film. In this range, the theoretical analysis and experimental results are in agreement with the Nusselt’s theory The formulas and experimental results are in accordance with the degree of comparison.According to the theoretical analysis of the design and calculation of the recommended formula can be used: Re = 0.025 (Ga ~ (1/3) / (Pr · K)) ~ (1.41) The results show that the exothermic coefficient is 36% higher than the pure theoretical result and is basically consistent with the experimental results, which is also similar to the empirical formula of many sources. This article also gives the more general The results of the analysis show that for some turbulent flow conditions, the error caused by neglecting the liquid film acceleration and convection of the liquid film itself is larger than that of the laminar flow, taking this factor into account The value of the exothermic coefficient is much lower than the value given by the Nusselt equation.The article includes the final results, which are tabulated.