瞬时畸变DC_θ的最大值预估

Estimatipn of the Maximum Values of Instantaneous Distortion Index DCθ

本文依据文[1]中提出的最大瞬时畸变值估算方法的基本思想,给出了具有极值运算的畸变指数DC_θ的最大瞬时畸变值的预估思路,从而使文[1]预估方法不独适用于美国P&W公司给出的一类畸变指数(K_(A2),K_(rad),K_θ),同时也适用于英国罗·罗公司给出的具有极值运算一类的畸变指数DC_θ等。文中还讨论了考虑脉动压力相关、瞬时畸变的概率分布等因素对DC_θ最大瞬时畸变值预估的影响,结果表明可提高预估精度。

In this paper,the statistical method for estimating the maximum instantaneous distor-tion in Ref. [1] is developed further to estimate the maximum values of the instantaneous distortion index DCθ in which the operation of peak values of dynamic pressures are in-volved. The effects of the correlation between fluctuating pressures and the amplitude probability density of the instantaneous distortion on the estimation are discussed. Com-parison between the estimated values and the experimental results shows that the newly developed method can quite accuratedly estimate the maximum value of the instantaneous distortion involving the operation of peak values of dynamic pressures.such as the distor-tion index DCθ. The accuracy of estimation of maximum instantaneous distortion can be improved further by considering the correlation between fluctuation pressure and the real amplitude probability density of the instantaneous distortion.