关键词: 变精度模型, 2.5D结构有限元模型, 初步结构设计, 静强度, 耐久性, 优化设计, 折叠机翼

Abstract: The accuracy limit of the finite element model makes durability analysis difficult to conduct in the classic preliminary structure design, leading to the potential problem of fatigue life shortage, increasing the difficulty in structural detail design, and even resulting in structure overweight. To address this problem, we propose the strength/durability preliminary structure design method based on the variable fidelity model technology and detail fatigue rating method. Durability analysis is advanced from the late structural detail design phase to the preliminary structure design phase. A folding wing is studied in this paper, and the stress level of the critical location (the joint between the inner and outer wings) is controlled based on the requirements of strength and fatigue. Multi-case optimization is conducted to ensure that the fatigue margin is larger than zero. Consequently, iteration design caused by fatigue life shortage is limited, and lighter weight structure design can be obtained more conveniently.

Key words: variable fidelity model, 2.5D structural finite element, preliminary structure design, static strength, durability, optimization desing, folding wing