代理模型在机翼油箱晃动适航审定中的应用

飞机飞行过程中,机翼油箱易受扰动或激励作用而产生低频晃动,引起机翼油箱壁面变形失效.本文将响应面代理模型引入飞机复合材料燃油箱晃动适航审定工作,以晃动频率、晃动幅值和油箱载液比为自变量,以油箱外壁面最大主应变峰值为响应,建立了油箱上下蒙皮响应面统计模型,给出油箱上下蒙皮最大主应变峰值与激励频率、幅值和油箱载液比等因素的显式响应函数.开展物理全尺寸试验和流固耦合数值模拟验证代理模型的有效性.结果 表明,上下蒙皮最大主应变峰值呈非线性趋势,存在最危险载液比使得主应变峰值最大化,且油箱破坏多发生在下蒙皮.

Application of surrogate model in qualification test for sloshed fuel tank

An aircraft wing fuel tank has low-frequency sloshing due to disturbances perturbations and excitations during flight, which may cause the deformation failure in the walls of a wing fuel tank.A response surface surrogate model is introduced to the qualification test for the sloshing of the composite fuel tank in an airplane.Taking the sloshing frequency, and the amplitude, and fuel load as design variables, the peak value of the maximum principal strains of the outer wall of the fuel tank as the response, we develop a statistical model for the top and bottom skins of the composite fuel tank and give the explicit response surface function of the peak strain depending on the sloshing frequency and amplitude, and the fuel load.The effectiveness of the surrogate model is verified by results of full-size experiments and solutions of fluid-solid coupling numerical simulations.The results show that there exists a worst fuel load to maximize the peak value of maximum principal strain, and the failure of the fuel tank mostly occurs on the bottom skin.