研究了载冷气泡和制冰溶液的直接接触换热过程,建立了对流换热微分方程,得到了努塞尔数和雷诺数、普朗特数的传热关联式,通过实验数据验证了模型的准确性。利用传热关联式,针对换热过程的熵产作了分析,在以气泡直径作为换热特征尺寸下,换热过程中熵产数随着雷诺数的变化存在最小值。研究为直接接触式对流换热过程的优化提供了理论基础。
In terms of direct-contact heat transfer process between cold air bubbles and immiscible liquid,the convection heat transfer equation was established and solved numerically. A correlation between Nu and Re as well as Pr was obtained, and the validation of the model was verified by comparing the theoretical value and the experimental data. Entropy generation during the heat transfer process was studied. The variation of entropy generation rate was presented regarding Re. An optimal Re would lead to a minimum entropy generation during the heat transfer process. The research provides a theoretical basis of optimizing the direct-contact heat transfer process.