作　　者： ; ; ;

机构地区： 中国科学院广州能源研究所

出　　处： 《中国工程科学》 2007年第12期86-93,共8页

摘　　要： 以甲醇为工质,在不同进口温度、质量流率、热流密度和倾角下,对低高宽比矩形微通道中流动沸腾压降特性进行了研究,并分别采用均相模型和分相模型对通道压降进行了计算。通过对比实验结果与计算结果发现,均相模型中两相平均粘度的计算应当采用Dukler公式,用其他计算式时误差较大;利用Lockhart- Martinelli关系式进行的分相模型计算发现,现有C值计算公式,如Chisholm,Lee and Lee,Mishima及Qu and Mudawar等,都不能用于预测该实验中低高宽比微通道的两相压降。实验发现当通道中含气率相对较高时,汽液两相间相互作用随x升高而减小,需采用一随质量流率减小而减小的C值计算式。通过实验提出了基于Mishima公式的C值计算式,用该公式得到的计算值与实验结果符合较好,平均相对误差仅为16.9%。 Pressure drops of flow boiling in a single microchannel having low aspect ratio were studied with effects of the inlet temperature, mass flux, heat flux and the inclined angle using methanol as working fluid. The present experimental data were compared with the predictions of the homogeneous flow model and separated flow model respectively. The comparison indicates that the homogeneous flow model cannot predict the two-phase pressure drop well except using the two-phase viscosity model of the Dukler correlation. With the existing correlations for parameter C in Lockhart-Martinelli correlation such as Chisholm, Lee and Lee, Mishima, Qu and Mudawar , separated flow model also failed to predict the two-phase pressure drop in the microchannel of this study The experimental data in this work show that the interaction between vapor phase and liquid phase is decreased with the increasing quality when the quality reach a certain value , accordingly there needs a correlation for C which decreased with the decreasing mass flux . A new correlation to predict the two-phase flow pressure drop in microchannels was developed in the form of the Lockhart-Martinelli correlation . It includes the effect of the hydraulic diameter and the effect of mass flux on the two-phase flow pressure drop in microchannels . The new correlation developed in this study predicted the experimental data within a mean absolute error of 16.9%.

关 键 词： 压降特性 均相模型 分相模型 微通道 流动沸腾

领　　域： [动力工程及工程热物理] [动力工程及工程热物理]