单面加热竖直窄通道内环状流沸腾传热特性

Heat Transfer Characteristics of Annular Upward Flow in Vertical Narrow Channal Heated from One Side

基于汽芯的动量方程和液膜的质量和动量方程,建立了单面均匀热流竖直窄通道内环状流沸腾传热模型,利用数值法对方程组进行求解,得出了环状流区域的液膜厚度,并进一步预测了环状流两相沸腾传热系数。研究表明:模型预测的两相沸腾传热系数比Mahmound关联式计算值偏小;将不同工况下的291组环状流两相沸腾传热系数实验值与模型预测值进行对比,平均绝对误差为12.7%。

A model of annular flow regime for saturated flow boiling in vertical narrow channel heated from one side has been developed based on the monmentum equation of the vapor core and the mass and monmentum equations of the liquid film.Through solving the closed equations of proposed model by numerical method,the liquid film thickness of annular flow region can be obtained and the two-phase heat transfer coefficient of annular flow is further predicted.The result shows that the two-phase heat transfer coefficient of model predictions are lower than the calculated values given by Mahmound correlations.it shows good agreement between the predicted two-phase heat transfer coefficient and 291 experimental results under different working conditions,and its mean absolute error is 12.7%.