Free flight wind tunnel test similarity law derivation for light store separation from aircraft

• Main Authors: Fei Xue, Han Qin, Yuchao Wang, Zenghui Jiang, Xin Jin, Peng Bai
• Format: Article
• Language: English
• Published: SAGE Publishing 2019-05-01
• Series: Advances in Mechanical Engineering
• Online Access: https://doi.org/10.1177/1687814019853062

Based on the linear displacement motion similarity and angular displacement motion similarity, the similarity law for free flight test of light store separation from aircraft is deduced. The problem that the ideal test model is too light to be processed and the free flight separation test in wind tunnel is harder to achieve due to the model scaling is solved. The new similarity law was simplified reasonably, and the relationship equation between separation velocity and model mass was obtained. The wind-loaded state is simulated by computational fluid dynamics, and the real separation data of aircraft, the separation data of previous test methods, and the simulation data of different mass and different separation velocity trajectories of this similarity law are obtained. The improved effect of the new similarity law is verified by data comparison. The results show that by properly increasing the mass of wind tunnel test model, the difficulty of wind tunnel test can be greatly reduced while the separation trajectory is similar, and the angular displacement error can be guaranteed to be within acceptable range. In order to ensure better consistency between flight and free flight wind tunnel test, it solves the problem that similarity law can only be designed but cannot be realized.