摘要本文旨在研究局部后掠式栅格翼的减阻与气动特性。通过建立不同后掠角的单孔后掠式栅格翼以及多孔局部后掠式栅格翼模型,并在亚声速、跨声速以及超声速流场中对其进行数值仿真,得到一系列的压力云图、密度云图、速度云图和升力阻力曲线。分别对三种模型在马赫数为0。5、0。75、1。0、1。25、1。5和2。0,攻角为0°、2°、4°和6°条件下进行数值模拟仿真,以便研究不同气动结构的局部后掠式栅格翼在不同流场条件下的气动变化规律。结果表明,局部后掠式栅格翼,其后掠角的大小会对阻力的产生影响。本文模拟结果表面,在亚声速阶段60°后掠角栅格翼,相比与45°后掠角栅格翼阻力较大,然而在跨声速及超声速阶段,大后掠角有利于减少阻力。83067
毕业论文关键词 栅格翼 局部后掠 数值仿真 超声速
毕业设计说明书外文摘要
Title The study on the resistance characteristics of reduction of a local sweptback grid fin in supersonic field
Abstract This article is aimed at studying drag reduction and aerodynamic characteristics of local sweptback grid fins。 After establishing models of single-hole sweptback grid fins and multi-hole local sweptback grid fins at different sweep angles, simulation can be carried on accordingly under three kinds of conditions: subsonic flow field, transonic flow field and supersonic flow field, and then a series of curves such as pressure nephogram, density nephogram, velocity nephogram, resistance curve and lift curve can be acquired。 Numerical simulations are carried out on these three models respectively at different Mach and attack angle, which provides convenience for the research on the rule of aerodynamic change under different flow conditions。 It turns out that the size of sweep angle of local sweptback grid fins has an impact on resistance of grid fins at 60°sweep angle is bigger than that at 45°sweep angle in subsonic flow stage, however, in transonic flow and supersonic flow, the large sweep angle will be in favor of reducing the resistance。
Keywords grid fin local sweptback numerical simulation
目 次
1 绪论 1
1。1 课题研究背景 1
1。2 栅格翼的优点与不足 1
1。3 栅格翼的几何参数 2
1。5 本文的主要工作 5
2 理论基础与概念 7
2。1 激波理论 7
3 数值仿真 13
3。1 几何建模 13
3。2网格划分 15
3。3Fluent求解 22
3。4计算结果后处理 23
4计算结果与分析 25
4。1单孔45°后掠角栅格翼气动特性分析 25
4。2单孔60°后掠角栅格翼气动特性分析 29
4。3后掠角对栅格翼气动力参数的影响 32
4。4多孔栅格翼气动特性分析 34
结论 40
致谢