应用计算流体力学软件FLUENT对一小型管壳式换热器的流动与传热问题进行了三维数值模拟.换热器壳体直径为130 mm,12根φ20 mm×1 500 mm的换热管正方形排列,折流板为30％缺口的弓形折流板,模拟了3种不同折流板间距的情况.模拟过程采用雷诺应力湍流模型,压力速度耦合选用SIMPLEC格式,压力方程的离散选用Standard格式,其他方程的离散均选用QUICK格式.数值模拟结果表明:减小折流板间距对总体传热系数的增加不太明显,但却显著增加了壳程的流动阻力.最后应用Bell法对3种不同折流板间距的数值模拟结果进行了校核,他们之间的最大误差为6.57％,表明数值模拟结果准确可靠.%A three-dimension numerical study on the heat transfer and fluid flow of a small shell-and-tube heat exchanger is performed by using the commercial CFD software package FLUENT. The shell diameter of the heat exchanger is 130 mm, which has twelve ψp20 × 1500 mm tubes arranged by square mode, and a segmental baffle with 30% cut, simulating three different baffle spacing. The Reynolds stress model for turbulent flow, SIMPLEC scheme for pressure-velocity coupling, standard scheme for pressure equation discretization and QUICK scheme for other equation discretization are selected in this numerical study. The numerical results show that the overall heat transfer coefficient increases relatively small by decreasing the baffle spacing, but the shell drag increases significantly. Finally, the numerical result of the three different baffle spacing is checked by Bell method, and their maximal deviation is 6. 57%, which confirmed the numerical result. The numerical method can be utilized further to optimize the internal structure and enhance the overall performance of the heat exchanger.
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