异形片式倾斜折流栅换热器壳程强化传热数值模拟

Numerical simulation of shell side heat transfer enhancement for special-shaped inclined baffle heat exchanger

采用CFD软件FLUENT,Standard k-ε模型,借助数值模拟方法对异形片式倾斜折流栅换热器和常规帘式折流片换热器流动传热性能进行研究,并利用场协同理论分析异形片式倾斜折流栅换热器的折流栅不同倾斜角度对壳程传热性能的影响。结果表明:壳程雷诺数在6000—10000范围内,同常规帘式折流片换热器相比,异形片式倾斜折流栅换热器折流栅与折流片平行排布时,壳程传热系数和综合性能分别增加12.7%—13.9%和6.4%—7.6%;折流栅和折流片交错排布时,壳程压降降低18.45%—19%,壳程综合性能略高于常规帘式折流片换热器;异形片式倾斜折流栅换热器折流栅倾斜25°时,壳程传热系数和综合性能最好,且速度场和温度场协同性最优,因此25°为异形片式倾斜折流栅换热器最优倾角。

The flow characteristic and heat transfer performance of special-shaped inclined and conventional shutter baffles heat exchangers were compared by numerical simulation with standard k-εmodel of CFD analysis software FLUENT.In special-shaped inclined baffle heat exchanger,the influences of heat transfer performance of shell side with different inclination angles were analyzed through field synergy theory.The results indicate that when the grid-baffles and baffles of special-shaped inclined baffle heat exchanger are arranged in parallel,the heat transfer coefficient and comprehensive performance of the shell side are 12.7%-13.9%and 6.4%-7.6%higher than that of conventional shutter baffles heat exchanger in the range of Reynolds number 6 000-10 000.When the grid-baffles and baffles of special-shaped inclined baffle heat exchanger are staggered,the pressure drop of the shell side decreases by 18.45%-19%,and the comprehensive performance of the shell side is slightly higher than that of the conventional baffle heat exchanger.When the inclination baffle angle of special-shaped inclined baffle heat exchanger is 25°,the heat transfer coefficient and comprehensive performance of the shell side are the best,and the synergy of velocity field and temperature field can be optimized to enhance heat transfer,the optimized inclination angle of baffle is 25°.