动导数是飞行器稳定性和操作性分析的原始输入参数。目前的计算方法主要包括工程方法和非定常CFD数值方法。前者虽具有较高的效率,但精度较低,后者则计算量较大。当地流活塞理论结合了CFD技术高精度和经典活塞理论高效率的优点。采用基于定常CFD技术的当地流活塞理论,发展了一种高效、高精度的超音速、高超音速飞行器动导数的计算方法。论文以纵向刚体模态为例推导了动导数的计算公式。通过两个国际标模算例的对比验证,证明了该方法的正确性和计算精度。
Dynamic derivatives are the original input parameters for stability and maneuverability analysis in aircraft design. Engineering methods and unsteady CFD methods are the main techniques for calculating dynamic derivatives at present. For the two methods, the former has higher efficiency but with lower accuracy, while the latter requires high computational cost. The local piston theory combines the advantages of high precision of CFD technolo- gy and high efficiency of classical piston theory. Local piston theory based on steady CFD method is used to calcu- late dynamic derivatives efficiently and accurately for supersonic and hypersonic aircraft. The formulas of dynamic derivatives are derived for rigid symmetric modes. Comparison with the experiment data of two standard models proves preliminarily that our method for calculating supersonic and hypersonic dynamic derivatives attains good precision at relatively lower computational cost and is thus indeed effective.