圆孔状折流板换热器壳程流体流动与传热特性的数值研究

Numerical Study on the Shell Side Fluid Flow and Heat Transfer Characteristics of the Heat Exchanger With Round Hole Baffle Plates

传统弓形折流板换热器壳程流体横向冲刷换热管时存在振动大、压力损失大和易结垢的缺点,为了克服上述缺点,本研究在弓形折流板的基础上有规律的开圆孔,并对其运用CFD软件Fluent进行数值模拟,研究其壳程流体流动与传热特性。本文通过数值模拟得出：折流板上开圆孔后,壳程流体流速更加均匀,有效地消除了流动＂死区＂,换热器平均压力损失降低了46.7%-150%,平均努赛尔数提高了2.7%-10.2%,速度矢量与温度梯度的夹角变小,协同性更好。

There are some shortcomings including heavy vibration, big pressure loss and easy fouling in traditional segment baffle heat exchanger when shell side fluid flows across heat exchange tube.In order to overcome the above shortcomings, the segmental baffle was drilled holes regularly, and the flow and heat transfer of the fluid in the shell side were studied by numerical simulation with CFD.The results show that the baffle plate with holes can make the fluid velocity more uniform distribution in the shell side, and can effectively eliminate the ＂dead zone＂,the pressure loss is reduced by 46.7%~150% on average,the average Nusselt number is increased by 2.7%~10.2%,the angle between velocity vector and temperature gradient decreases, which indicates better cooperativity.