水平矩形通道内开孔折流板强化换热的实验研究

Study of heat transfer enhancement in horizontal rectangular channel with staggered holed baffles

Re数在500～15 000范围内,对矩形通道内交错布置多个开孔折流板的强化换热特性进行了实验研究,分析了开孔密度对通道强化换热的影响,并与设置不开孔折流板通道的实验结果进行了对比分析.实验结果表明:开孔折流板具有较好的强化换热效果,随着雷诺数Re的增加,换热效果逐步增强;同未开孔折流板相比,开孔密度为2.51 %的折流板的强化换热效果最好,在测试的Re数范围内,其平均Nu可以增加59 %,最大可以提高到2倍.最后,在实验数据基础上,关联得出了一个换热准则关联式,可以用作开发新型换热器的设计计算依据.

With Re Number ranging between 500 and 15 000, the characteristics of heat transfer for several different holed baffles installed in rectangle channels have been studied experimentally. In this paper, the influence of some hole＇s geometric parameters on the channel＇s heat transfer coefficient was discussed. The experimental data show that the rectangle channel＇s Nu Number increases with the Re. The holed baffle is a new kind of intensive heat transfer technology. Compared with the normal baffle, the best heat transfer enhancement occurs when the ratio of hole＇s area to the baffle total area is equal to 2.51%, its average Nu among the test Re range improves by 59 %, with the maximum of 100%. Finally, based on the experimental data, a correlation for predicting the heat transfer coefficient has been acquired and it can be used to develop the new type heat exchanger.