Studies on performance evaluation method of a wing in surface effect

地效翼船（WIG）或地效翼船（WISE S）有望成为未来海上高速飞行器之一。为了避免水面效应的非线性，避免船舶在海上发生意外运动，需要发展运动中具有平直特性的翼段。地效翼船绕流流场的计算公式和近似求解方法（1）三维地效翼船大展弦比近似从摄动法的角度出发，研究地效翼船的三维效应，由于升力线理论中的尾涡下洗效应可以忽略，因此构造了考虑翼尖效应的环量分布局部解，并在翼展中部采用二维解。这两个领域的复合解决方案显示出良好的协议，在整个地区的计算解决方案。(2)改进了二维地效翼船在规则海中的非定常运动近似解方法，求解了二维地效翼船的辐射和绕射问题，基于入射波的船舶运动相位延迟不仅依赖于基于整个地效翼船长度的常规频率比，还依赖于基于一个长度缺陷而定义的频率参数.二维地效翼梁的形状优化设计目的是利用非线性规划方法获得升力系数最大的二维地效翼梁截面。在一定的限制条件下，得到了波形截面.应用考虑兴波效应的绿色函数，对地效翼绕流场进行了二维WIGA兴波效应数值分析。用线性涡格元模拟厚地效翼片给出了较好的结果。

WIG( Wing In Ground effect) or WISE S (Wing in Surface Effect Ship) is expected in future as one of high speed vehicles on seaway. Wing section with flat characteristics in motion has to be developed to avoid unexpected ship motion in sea due to nonlinearity of surface effect.From 3 points of view, studies on performance evaluation method of WIG are made as followings :1. Formulation and approximate solution method of flow field around a WIG(l)High aspect ratio approximation of 3D WIGFrom the view point of perturbation method, a study is made to clear 3D effects of WIG.Since the downwash effect due to the trailing vortex seen in the lifting line theory is negligible, local solutions of circulation distribution with wing tip effect are constructed and 2D solution is applied in the mid span area. Composite solution of both areas shows good agreement in whole area with a computational solution.(2) Unsteady motion of 2D WIG in regular seaApproximate solution method is enhanced to solve a radiation and diffraction problem of 2D WIG.Phase late of ship motion based on incident wave is dependent not only on the ordinary frequency rate based on whole WIG length but also on the newly defined frequency parameter based on a deficient length in appearance.2. Shape optimization of 2D WIGIt is intended to obtain a 2D WIG section with maximum Lift coefficient by using a nonlinear programming method. Under some restricted condition a wavy cross section is obtained.3. Wave generation effect of 2D WIGA numerical analysis of flow field around a WIG is made applying Green's function with the effect of wave generation. Linear vortex lattice element to represent a thick WIG gives good results.