单次扫描空间推进算法在高超声速流动中的适用性研究

通过高超声速流动的三个典型算例,研究单次扫描空间推进(SSPNS)算法计算高超声速流场气动力、气动热的精度以及适用范围.结果表明:①在楔角不大于15°,流动无流向分离的情形下,用SSPNS算法计算压缩楔板流动是可行的;②对绕圆锥流动的计算表明,SSPNS算法对横向分离的模拟是值得信赖的;③对于12.攻角以内的小攻角绕翼流动,SSPNS算法的精度与时间迭代法基本一致;④空间推进法计算速度较时间迭代CFD(计算流体动力学)方法提高1～2个数量级.

Study on the reliability of a single-sweep space marching algorithm for hypersonic flows

The accuracy and reliability of a single-sweep space marching parabolized Navier-Stokes (SSPNS) algorithm for aeroforce and aeroheating prediction in hypersonic flow fields were investigated through three typical cases: Hypersonic Laminar Compression Corner Flows, Circular Cone at Angle-of-Attack and Two-dimensional Wing at Angle-of-Attack. The results suggest: (1) It is feasible for the SSPNS algorithm to predict hypersonic Laminar Compression Corner Flows with wedge angle smaller than 15°. A bigger wedge angle causes obvious streamwise flow separation which leads to considerable error. (2) For 10° cone flows (biggest attack angle 24°), there are only transverse separations in which case the numerical results of the SSPNS algorithm are reliable; (3) For the flows over a two-dimensional wing with attack angle smaller than 12°, the accuracy of the SSPNS algorithm corresponds with that of time-iterative algorithm; (4) Comparison to the traditional time-iterative Full Navier-Stokes, the SSPNS algorithm shows 1~2 order of magnitude of computational speed faster and considerable storage saving.