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针对椭圆管矩形翅片间的空气流动特性,将应用于直接空冷电站椭圆管矩形翅片的几何中心相对于椭圆管的几何中心偏置.针对不同偏心距离x,以及不同入口风速u,得到空气侧对流换热系数h和压差P随u的变化规律.模拟结果表明翅片的偏置会对着空气侧的流动与换热产生不同影响:翅片向前偏置,低速尾流区对翅片表面换热的影响减小,空气侧总的表面传热系数h增加,且向前偏心距离△x越大,h越大;翅片向后偏置,低速尾流区造成翅片表面局部换热的恶化,以及压力损失的增加.利用PEC对低速尾流区对矩形翅片椭圆管空气侧的换热与流动的综合影响进行了比较.“,”Based on the air flow characteristics between the rectangular fins of elliptical tube,it was supposed that the geometric center of rectangular fin deviated from that of elliptical tube.The variations of air-side surface heat transfer coefficient h and pressure dropΔp with different eccentric distancesΔx and inlet air flow velocities u were obtained.The simulating results indicated different influences of eccentric distance on heat transfer and flow performances.Setting the rectangular fin forwards,significant heat transfer enhancement could be acquired because of the weaken of the wake turbulence region.On the contrary,both deterioration of heat transfer and flow performances were found while setting the rectangular fin backwards.Performance evaluating criterion(PEC) was employed to access the influences of the wake turbulence region on air flow heat transfer with different eccentric distances.