高超声速钝锥体俯仰阻尼导数影响因素分析

The research on the influence of hypersonic blunt cone pitching dynamic derivatives calculation

采用非定常双时间步长方法、刚性旋转动网格技术,结合空间隐式格式数值分析了高超声速钝锥体定常与非定常流场特征,并运用最小二乘法辨识出钝锥体的俯仰阻尼导数。通过与相应的实验数据、工程估算值进行比较,分析并验证了壁面网格雷诺数、钝头比、攻角与质心位置对钝锥体俯仰阻尼导数的影响。同时采用五种差分格式,其中包含五阶精度WENO与高精度WNND格式,对钝锥体俯仰阻尼导数进行了计算,结果表明不同无粘差分格式对俯仰静导数影响较小,但不同格式之间俯仰动导数结果存在差异,分析认为差分格式之间不同的粘性分辨率应是差异的主要来源。

The steady aerodynamic coefficient and pitching dynamic derivative of blunted conical models in hypersonic flow was validated by using implicit scheme, with the technology of the dual time stepping, rigid rotary grid deformation and least square method. Compared with the results from experiments and engineering method, the influence of the pitching dynamic derivative with different grid, bluntness ratio, angle of attack and the center of the gravity was investigated. Moreover, some of the key differences of the dynamic derivative reesults were derived from using different schemes, including high-order WEN0 and WNND schemes. The result shows that the viscid resolution of the scheme is the main source of the difference.