椭圆管矩形偏心波纹翅片倾角对换热性能影响的数值研究

摘要

The Fluent software was employed to carry out three dimensional numerical simulation on heat transfer performance of rectangular eccentric corrugated fin-and-oval tube heat exchangers with five differ-ent corrugated inclination angles,with facing velocity ranging from 0.5 m/s to 4 m/s.The results indicate both the facing velocity and corrugated angle can affect such indexes as Nusselt number on surface of the rectangular eccentric corrugated fin-and-oval tube heat exchangers,average differential pressure loss and finned tube heat transfer performance influence factor.The comprehensive heat transfer performance of the rectangular eccentric corrugated fin-and-oval tube heat exchangers turned worse with an increase in corru-gated inclination angle.Through analyzing variation of the Nusselt number Nux on finned tube surface,we can predict that properly increasing the front windward corrugated inclination angle and reducing the rear area corrugated inclination angle not only can enhance the heat transfer but also can reduce the resistance loss.Furthermore,the reliability and validity of the simulation model were checked by experimental exami-nation,and the simulation results can provide some practical and reliable theoretical basis to the research of finned tube heat exchangers.%应用Fluent软件对5种波纹倾角的椭圆管矩形偏心波纹翅片在迎面风速v为0．5~4 m/s范围内的换热性能进行了三维数值模拟，并对计算模型的可靠性和有效性进行了实验验证.研究表明，迎面风速和波纹倾角θ均会对翅片表面努塞尔数Nu、压差损失Δp和翅片管综合换热性能j/f产生影响，椭圆管矩形偏心波纹翅片的综合换热性能随着波纹倾角θ的增加而变差.分析沿流动方向翅片耦合面的平均Nux 值的变化趋势可预测适当增加翅片前端波纹倾角、减小翅片后部区域波纹倾角，既能增强换热性能又可减小阻力损失.