摘要
根据气动参数估算的需要,分析了样条函数的基本概念、方程及三次插值样条函数在参数估算中的应用,以某歼击机全机平衡升力线斜率对马赫数的偏导数为例,用三次插值样条函数对其进行了估算。为了对比起见,又用常用的最小二乘多项式分段拟合方法对其进行估算。估算结果表明,采用样条函数进行参数估算,精度高,且分段点处函数及其导数连续,满足了数字仿真和模拟运算的要求;而最小二乘多项式分段拟合不仅精度低,而且在分段点处函数及其导数不连续,给使用带来不便。因此,样条函数是估算气动参数的一种十分有效的方法。
Abstract The estimation of the aerodynamic derivative is a important job in the research of flying performances and qualities. This paper presents a new method-----spline function method to estimating aerodynamic derivative. At first , the paper shows principle of spline function, then applies cubic spline interpolation to estimating aerodynamic derivative and creating a database software package. The conclusion is that the spline function method is an effective mathematical method of estimating continuous and accurate aerodynamic derivative. And it also presents the shortcomings of least square fit method.
出处
《飞行力学》
CSCD
北大核心
1996年第3期61-65,共5页
Flight Dynamics
关键词
样条函数
气动导数
飞机
气动参数
估算
Spline function Least square method Aerodynamic derivative