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采用多阶段曲线拟合技术,对双平面拍摄风洞自由飞试验获得的高超声速下非旋转钝锥角运动观测值作了拟合,获得了与试验观测值重合度较好的拟合曲线,进而实现了对试验模型非线性角运动轨迹的重构,获得了5次试验的复攻角和总攻角曲线,并进而对非旋转钝锥非线性角运动的特点和规律进行了分析。结果分析表明:模型复攻角曲线可能逆时针方向转动也可能顺时针方向转动,甚至可能改变转动方向;复攻角曲线多呈“椭”圆锥运动,且椭圆运动的长轴在大小和方向上均可能发生变化;总攻角幅值呈振荡变化,但多呈总体上减小的趋势;由于角运动的非线性特性,同样的试验模型在不同的预置攻角情况下其角运动特性也呈现出很大的不同。
The multiscale curve fitting technique was used to fit the observations of non-rotating blunt cone angular motion at hypersonic velocity obtained from the free-flight test of wind tunnel in bi-plane shooting. The fitting curves with good coincidence with the experimental observations were obtained, The reconstructed non-linear angular trajectory of the experimental model is achieved. The complex attack angle and the total attack angle curve of the five experiments are obtained, and the characteristics and regularities of the nonlinear angular movement of the non-rotating obtuse cone are analyzed. The results show that the complex attack angle curve may rotate anticlockwise or clockwise, and may even change the direction of rotation. The complex attack angle curve mostly shows “elliptical” conical motion, The amplitude of total attack angle changes oscillatory but tends to reduce generally. Due to the nonlinearity of angular motion, the same test model has different angular movement characteristics under different preset angles of attack Showing a big difference.