单弓形小圆孔折流板换热器壳程流体特性

Flow and heat transfer characteristics for shell side of single bow baffle plate with small holes heat exchanger

基于流体力学基本原理和周期性充分发展模型理论对换热器壳程流体进行分析。提出一种单弓形小圆孔折流板管束支撑结构,即在传统的单弓形折流板上开孔,减小传热死区和换热管束的振动。利用CFD技术对这种单弓形小圆孔折流板换热器壳程流体的流动和传热性能进行数值模拟。分析结构和操作参数对单弓形小圆孔折流板换热器综合换热性能的影响,利用多元线性回归推导其壳程压降和对流换热系数的准数关系式。研究结果表明：单弓形小圆孔折流板换热器的壳程压降、对流换热系数和综合换热性能分别为传统单弓形折流板换热器的34.25%-50.86%,73.17%-95.29%和1.4389-2.7822倍。

The shell-side fluid of heat exchanger was analyzed based on the basic principle of hydromechanics and theory of the periodically fully developed model. A supporting structure for single bow baffle with small holes was proposed, namely holes were made on the traditional single bow baffle to reduce the heat transfer dead zone and release the vibration of the heat exchange pipes. The heat exchangers with the single bow baffle with small holes and the single bow baffle respectively were simulated through CFD. The effect of the structure and operation on the comprehensive performance for the single bow baffle with small holes heat exchanger was analyzed. Both the correlative equations of the convective heat transfer coefficient and the pressure drop were deduced through the multiple linear regression. The results show that the pressure drop of the single bow baffle with small holes heat exchanger is only 34.25%-0.86% of that of the traditional single bow baffle heat exchanger, and the convective heat transfer coefficient of the former is 73.17%-95.29% of that of the latter. Therefore, the comprehensive performance of the former is 1.438 9-2.782 2 times of that of the latter.