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通过对水在水平管束管外池沸腾的实验研究，探讨了沸腾换热系数随热流密度及沿管排高度变化的规律和内在机理．由实验结果发现：管束中各排测量管的沸腾换热系数明显高于单管池沸腾的情况；管束沸腾时存在管束效应，即随管排位置增高，起始沸腾点提前，沸腾曲线上移，沸腾换热系数增大；这种管束效应在部分核态沸腾时较强，而在充分发展核态沸腾时较弱；管束池沸腾的强化传热应归因于“滑移汽泡”及“诱发自然循环对流”机制．此外，还得出了管束池沸腾换热系数的经验关系式．
Through the experimental study on the boiling of water outside the horizontal tube bundle, the law and internal mechanism of the boiling heat transfer coefficient with the heat flux density and height along the tube row are discussed. From the experimental results, it is found that the boiling heat transfer coefficient of each measuring tube in the tube bundle is significantly higher than that of single-tube boiling; the tube bundle effect exists when the tube bundle is boiled, that is, as the tube row position increases, the initial boiling point advances and the boiling curve shifts , And the boiling heat transfer coefficient increases. The tube bundle effect is stronger at some nucleate boiling and weaker at full development of nucleate boiling. The enhanced heat transfer of tube bundle boiling is attributed to “slipping bubble” and “Induce natural circulation convection” mechanism. In addition, we obtained the empirical relation of the boiling heat transfer coefficient of the bundle.