等热流矩形通道内柱面翼涡发生器的强化换热特性研究

Study of the Intensified Heat Exchange Characteristics of a Cylindrical Wing Vortex Generator in a Rectangular Channel With a Constant Heat Flow

在等热流条件下,实验研究了矩形通道内设置平直、柱面翼型涡发生器(VGs)对综合换热性能的影响。以(Nu/Nu0)/(f/f0)1/3作为评价涡发生器综合换热性能的因子,结果表明:呈流线型的椭圆柱面翼型涡发生器的综合换热性能优于平直翼型。进一步考察了斜截角α、攻角β和前沿间距S对综合性能的影响。斜截角α=20°的综合换热性能较佳;Re=650～2900工况下,攻角β=0°的综合换热性能最强;随着Re的增大,β=45°和β=60°的综合换热性能显著增强;前缘间距S=30 mm时,椭圆柱面梯形翼(α2=20°)的综合换热性能最高。根据实验结果,对椭圆柱面翼进行实验关联式的拟合,为工程设计提供参考依据。

Under the condition of a constant heat flow,experimentally studied was the influence of the placement of a plane and cylindrical wing vortex generator on the comprehensive heat exchange performance.With(Nu/Nu 0) /(f/f 0) 1 /3 serving as a factor for evaluating the comprehensive heat exchange performance of a vortex generator,it has been found that the comprehensive heat exchange performance of a streamlined cylindrical wing type vortex generator is superior to that of a plane and straight wing type one.Furthermore,the influence of the inclination angle α,attack angle β and interval at the leading edge on the comprehensive performance was investigated.When α = 20 degrees,the comprehensive heat exchange performance will be relatively good.Under the condition when Re = 650-2900,the comprehensive heat exchange performance at β = 0 degree will be the best.With an increase of the Re,the comprehensive heat exchange performance at β = 45°and β = 60°will be markedly improved.When the interval at the leading edge S = 30 mm,the comprehensive heat exchange performance of the elliptical cylindrical trapezoidal wing(α 2 = 20 degrees) type vortex generator will be the best.On the basis of the test results,a fitting of an experimental correlation formula for the elliptical cylindrical wing type vortex generator was performed to offer reference and basis for engineering design.