Shell side flow in traditional segmental baffle heat exchangers has large dead zone, which leads to the decrease of heat transfer area and increase of resistance loss. In order to improve heat transfer efficiency of segmental baffle heat exchangers, a novel louver baffle supported tube bundle configuration was proposed. The heat transfer and flow resistance of confined external flow within louver baffle supported tube bundles were investigatedby three-dimensional numerical simulation. The results show that the flow field is uniform and has less dead zone. Compared with shell-side confined external flow, pressure drop of the proposed confined external flow decreases by 17.1%~45.7%, which greatly improves energy consumption. Moreover, the pressure drop decreases with the decrease of inclination angle, with the best overall performance at 45o. The maximum heat transfer coefficient of the new confined external flow is 25.9% higher than that supported by segmental baffles under same pressure drop. This study can help the design and development of shell and tube heat exchangers with low power consumption.%针对传统弓形折流板支撑多管束受限外流流动死区大,压降高的问题,提出新型斜百叶片折流板支撑多管束结构.通过全三维数值模拟,研究斜百叶片支撑多管束受限外流的传热和阻力特性,获得其局部流场,分析了不同斜百叶片倾角对其性能的影响.研究结果表明:斜百叶片支撑多管束受限外流流场分布均匀,流动死区小;与传统弓形折流板支撑的情况相比,压降减小17.1%~45.7%,功耗显著降低,且随斜百叶倾角减小而减小;倾角为45o 时具有最优综合性能,相同压降下的传热系数比弓形折流板支撑的情况可提高25.9%.研究结果可为新型低功耗管壳式换热设备的开发和设计提供参考.
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