基于应变-弯矩的半柔壁喷管大挠度变形重构研究

A large-deflection deformation reconstruction method for semi-flexible plate nozzle based on strain-moment relationship

为提高超声速风洞半柔壁喷管健康监测能力,发展了基于应变-弯矩关系的柔性壁板大挠度变形重构方法。以超声速风洞多支点半柔壁喷管为研究对象,建立了型面组件力学模型,推导了柔性壁板型面曲线的微分方程,给出了柔性壁板大挠度变形的椭圆积分表达式及解析解。基于薄板变形理论对重构算法进行了修正,采用有限元仿真分析了修正效果,修正后的最大偏差仅为修正前的10.78%。利用0.3 m半柔壁喷管实验平台开展实验验证,结果表明:在6种马赫数工况下,所提方法的变形重构结果与实验结果均能良好吻合,在喷管喉道位置坐标偏差约为结构变形的6.12%,验证了所提变形重构算法的有效性和准确性。

To enhance the health detection capability of the semi-flexible plate nozzle in a supersonic wind tunnel, a large-deflection deformation reconstruction algorithm for a semi-flexible plate nozzle based on the strain-moment relationship is developed. The multi-jack semi-flexible plate nozzle in the supersonic wind tunnel is studied;its mechanical model of contour assembly is established. The differential equation of flexible plate contour curve is deduced, and the elliptic integral expression of the flexible plate deformation is given. Based on the deformation theory of a rectangular thin plate, the deformation reconstruction algorithm is modified, and its correction effect is simulated and analysed with the finite element method. The maximum deviation after correction is only 10.78% compared with that before correction. The 0.3 m semi-flexible plate nozzle is used as the experimental platform to carry out the experimental study. The experimental results show that under the 6 Mach number, the large-deflection deformation reconstruction results based on strain-moment relationship are in good agreement with the experimental results. The coordinate deviation of the nozzle throat position is about 6.12% compared with the structural deformation, thus verifying that the deformation reconstruction algorithm in this paper is effective and accurate.