水平管外降膜流动液膜厚度数值模拟

建立了水平管外液体降膜流动过程的物理数学模型并对其进行了数值模拟研究,将模拟结果与文献中的理论值和实验值做了比较,变化趋势吻合较好.通过计算不同雷诺数下沿管壁周向的液膜厚度及液膜分布情况,分析了结构和流动参数对液膜厚度与分布的影响规律.结果表明:液膜厚度随雷诺数的增大而增大;当雷诺数一定时,管壁周向液膜厚度呈先减小后增大趋势并随管间距的增大而减小,并且随着雷诺数的增大,管壁周向液膜波动增大且易出现"干区".

Numerical simulation of falling film thickness around a horizontal tube

A systematic introduction of the junction structure of bond graph and matrix transforming modeling method is given. Scientific and practical values of the theory and the modeling method are demonstrated through an in|depth analysis, then exemplified by a case of pressure regulating system in pilot relief valve. Bond graph model and its corresponding mathematical model are bridged by the matrix transforming method, which serves to validate the bond graph model through rigorous mathematical method. Conditions in favor of the modeling method, limitations and corresponding issues are also discussed which may provide valuable reference for the study and application to the related area.