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为了研究平流层飞艇尾部动量边界层厚度与尾涡结构,应用LES(大涡模拟)方法计算了零攻角工况下飞艇绕流场,并对LOTTE和M-LOTTE两种飞艇进行了对比分析.采用Q分布和涡量描述回转体尾涡结构,根据Q分布可以确定M-LOTTE飞艇较LOTTE飞艇尾部分离区显著减小;并分析了回转体的轴对称曲面动量边界层厚度对飞艇气动阻力的影响,随着飞艇尾部厚度逐渐减小,动量边界层厚度逐渐增大,M-LOTTE飞艇尾部动量边界层厚度明显小于LOTTE飞艇.飞艇尾部动量边界层厚度分布说明了MLOTTE飞艇的总阻力系数较LOTTE飞艇降低17.2%的原因,同时也表明飞艇尾部形状对飞艇气动阻力影响较大.
In order to study the thickness of tail boundary vortex and the tail vortex structure of the airship in the stratosphere, a LES (Large Eddy Simulation) method was used to calculate the flow around the airspeed at the zero-angle of attack (AOA) and the comparative analysis of LOTTE and M-LOTTE The Q distribution and vorticity are used to describe the wake structure of swivel body. According to the Q distribution, the M-LOTTE airship can be significantly reduced compared with that of the LOTTE airship. The influence of the boundary layer thickness on the aerodynamic drag The thickness of the momentum boundary layer gradually increases with the thickness of the tail airship, and the thickness of the momentum boundary layer at the tail of the M-LOTTE airship is obviously smaller than that of the LOTTE airship.The thickness distribution of the momentum boundary layer of the airship shows that the total drag coefficient LOTTE airship to reduce the cause of 17.2%, but also shows that the airship tail shape aerodynamic drag greater impact.