【作者】 王效嘉； 田茂诚； 魏民； 衣秋杰； 李亚鹏； 贾文华；

【Author】 WANG Xiao-jia;TIAN Mao-cheng;WEI Min;YI Qiu-jie;LI Ya-peng;JIA Wen-hua;Thermal Sciences Institute in School of Energy and Power Engineering,Shandong University;

【机构】 山东大学能动学院热科学研究所；

【摘要】 该数值模拟建立了二维模型,研究了竖壁外含不凝气的蒸汽的凝结过程。计算结合改进的壁面冷凝模型和VOF模型对凝结过程中不凝气层的变化规律及液膜的演变形态进行瞬态计算。通过UDF将气相和液相的源项添加在控制方程中,同时将计算结果和实验结果进行对比证明了数值模拟结果的可靠性。计算结果表明,在凝结过程的初期会产生高浓度不凝气层,随着凝结过程的深入,不凝气扩散回主流气体;凝结液膜会出现波动,滑动及脱落等动态现象;凝结换热量占比可达90%以上,液膜热阻占总热阻的20%～26%。更多还原

【Abstract】 This study established a two-dimensional CFD model and numerically studied the condensation process of steam with non-condensation gas.The improved Wall Condensation Model(WCM) and Volume of Fluid(VOF) were combined to investigate the change law of non-condensation gas layer and liquid film.The source terms of steam and liquid film were added to the convergence equations through the UDF,and the reliability of this numerical simulation results was proved by comparing the calculated results with the experimental results.The calculation results showed that a high concentration non-condensable gas layer will be formed in the early stage of the condensation process,with the deepening of condensation process,the non-condensable gas gradually diffuses back to the mainstream.Meanwhile,the dynamic phenomena such as fluctuation,sliding and shedding of liquid film will occur.The condensation heat transfer accounts for more than 90%,and thermal resistance of liquid film accounts for 20%—26% in the total thermal resistance.更多还原