论文部分内容阅读
为了研究激波对气膜冷却效果的破坏机理,并消除这种影响,以平板壁面为基础设计了一种带有卸压槽的壁面结构。通过数值计算研究了主流马赫数为3.2,冷流马赫数分别为1.0、0.6和0.4三种工况下开槽壁面对激波破坏的抑制作用。结果表明,在有激波入射的条件下,开槽壁面比平板壁面具有更好的流场结构,可使激波导致的近壁气膜的分离区最多减小至原来的三分之一,并有效减弱气膜入射后在肩部产生的反向涡旋对,这很好地抑制了气膜的卷吸和与主流的掺混。计算显示开槽壁面最大能够使壁面冷却效率提高6%,且这种作用效果与通过卸压槽的气流流量大小有关。此外仿真结果表明,在相同条件下波前卸压较波后卸压效果更好。通过合理安排卸压槽位置及槽面宽度,可以将总压损失控制在合理范围内。
In order to study the damage mechanism of the shock wave on the film cooling effect and to eliminate this effect, a wall structure with pressure relief groove is designed based on the slab wall. The effects of slotted wall on the shock wave damage were studied by numerical calculation under the condition of the main Mach number is 3.2 and the Mach number of cold flow is 1.0, 0.6 and 0.4 respectively. The results show that the slotted wall has a better flow field structure than the slab wall in the presence of a shock wave, and the separation area of the near wall gas film caused by the shock wave can be reduced to a maximum of one third, And effectively reduce the reverse vortex generated in the shoulder after the gas film incident, which well inhibits the entrainment of the gas film and the blending with the mainstream. Calculation shows that the maximum groove wall surface cooling efficiency can improve the wall 6%, and this effect is related to the flow through the pressure relief slot flow rate. In addition, the simulation results show that under the same conditions wavefront pressure relief wave relief effect better. By reasonably arranging the position of the pressure relief groove and the width of the groove surface, the total pressure loss can be controlled within a reasonable range.