径向冷却通道截面特征长度对气冷稳定器性能影响

通过研究径向冷却通道截面特征长度的改变对气冷稳定器的冷态流场、冷却性能及流动损失的影响，为其进一步的优化设计提供参考依据。采用经过实验验证的CFD方法，对某气冷稳定器进行了数值模拟研究，在所研究的特征长度范围内，结果表明:特征长度的增加，减少了径向冷却通道下部的进气阻力，使得风兜引气率增加了667%；下部出气孔出流由于受到回流涡的影响，出流量明显低于上部出气孔，特征长度的改变对出流量分布的影响不大；特征长度的增加会加强径向稳定器近环形稳定器处的外壁面冷却效果，但是会减弱径向稳定器近中心锥处的外壁面冷却效果；特征长度的增加，使得出口总压恢复系数下降了0.086%，沿程总压恢复系数曲线向下移动。 

Effect of radial cooling channel sectional characteristic length on air cooled flameholder

To study the impact of radial cooling channel section characteristic length change on air cooled flameholder cooled flow field, the cooling performance and flow loss, and also provide reference for further optimization design, a numerical simulation was performed by using an experimentally validated CFD method. Within the range of the characteristic length, the results indicated that, increasing the characteristic length reduced the lower portion intake resistance of radial cooling channel, so the air pocket entraining rate caused an increase of 667%. Due to the impact of vortex, the mass flow of the vent holes at the lower portion was significantly lower than that at the upper portion. Changing characteristic length had little effect on the mass flow distribution. Increasing the characteristic length enhanced the outer wall cooling effect of radial flameholder adjacent to the ring flameholder, but weakened the outer wall cooling effect of radial flameholder close to the inner cone. Due to the increase of the characteristic length, outlet total pressure recovery coefficient decreased by 0086% and total pressure recovery coefficient distribution curve along the afterburner moved downward.