소형 위그선의 복합재 주익의 경량화 구조 설계 및 해석에 관한 연구

Abstract

In this paper, conceptual structural design of the main wing including aileron for a small scale WIG(Wing in Ground Effect) vehicle which will be a high speed maritime transportation system for the next generation in Rep. of Korea, was performed. The Carbon-Epoxy material was selected for the major structure, and the skin-spar with a foam sandwich structure was adopted for improvement of lightness and structural stability. As a design procedure for the present study, firstly the design load was estimated through the critical flight load case study, and then flanges of the front and rear spars from major bending loads and the skin and the spar webs from shear loads were preliminarily sized using the netting rule and the rule of mixture. Stress analysis was performed by a commercial FEA code, NASTRAN/PATRAN. From the stress analysis results for the first designed wing structure, it was confirmed that the upper skin between the front spar and the rear spar was unstable for the buckling. Therefore in order to solve this problem, a middle spar and the foam sandwich type structure at the skin and the web were added. After design modification, the structural safety and stability for the final design feature was confirmed. In addition to this, the insert bolt type structure with eight high strength bolts to fix the wing structure to the fuselage was adopted for easy assembly and removal as well as in consideration of more than 20 years fatigue life. Additional deign on aileron including joint structure between main wing and control surface was performed. The channel type spar, the foam sandwich skin structure and the lug joint were adopted for aileron design.