Numerical Study of a UAV with Tandem Wing under Gust Load Influence using Two-Way Fluid-Structure Interaction Method

This paper presents a new investigation of a tandem wing configuration under cruise and gust load conditions. A wing of a high-altitude long-endurance unmanned air vehicle (HALE UAV) is used as a case study. A two-way fluid-structure interaction (FSI) analysis is conducted. A numerical investigation is done by coupling the Computational Fluid Dynamics (CFD) and Computational Structural Dynamic (CSD) domains. A complex phenomenon is evaluated, i.e., flow interaction between front and rear wings. In addition, the structural response of the rear wing due to the gust disturbance and the interference of downstream flow from the front wing is studied. The variance of gust disturbance is based on the chance of occurrence. The results pointed out that for a more realistic, small gust with higher gust probability, the pattern of the structural response closely follows the gust pattern, i.e., the response reaches its peak similar to the gust shape. However, for a smaller chance of gust, i.e., higher gust amplitude, the structural response has some discrepancies and depicts a sharper trend toward its peak value due to a high change of angle of attack.