大展弦比大柔性机翼载荷分布求解的一种方法

大展弦比大柔性机翼在气动力作用下产生较大的弯曲和扭转变形,会引起明显的气动载荷重新分布。基于一种只具有2个广义转角自由度的梁单元模型,提出了一种大展弦比大柔性机翼载荷重新分布的新方法。该方法将大柔性机翼弯曲变形的几何非线性问题转化为线性问题,同时,基于弯曲变形结果,可在局部坐标系下进行机翼扭转变形求解,避免了整体坐标系下扭转变形的几何非线性问题。综合来看,该方法可将具有明显几何非线性效应的大展弦比大柔性机翼的载荷重新分布问题转化为线性问题,且计算量小,效率高,非常适合工程实用。通过与大柔性悬臂梁解析解的对比,验证了本文方法的正确性和有效性。

A method for aeroelastic load redistribution of very flexible wing with a high-aspect-ratio

Very flexible wing of the aircraft with a high-aspect-ratio under goes large bend and twist deformation, which leads to a distinct redistribution of the aeroelastic load. A new method is developed for the aeroelastic load redistribution of the flexible wing based on a new beam element with only two degree of freedoms(two general bend angles). By using the beam element, the complex geometrically nonlinear computation for the bend deformation of the wing is converted to be a simple linear problem. Meanwhile, the twist deformation of the wing can be linearly solved in the local coordinate system, avoiding the complex geometrically nonlinear computation in the global coordinate system. In a word, the present method simplifies the aeroelastic load redistribution of the flexible wing through transforming a geometrically nonlinear problem to be a linear one. The results are in a very good agreement with the analytical solutions and indicate that the present method is accurate and efficient for engineering practice.