Aerodynamics and Flight Stability Evaluation of SACCON UCAV through RANS Simulations

Abstract

For the determination of aerodynamics and flight stability evaluation of complex and modern geometries, designers usually move towards the wind tunnel experiments. But modern designs are complex and testing process for them is becoming a bit complex too. Similarly, there are some other issues linked with wind tunnels which include cost and time factor. On the other hand, Computational Fluid Dynamics (CFD) helps in reducing the physical limitations of the system that are linked with the price, schedule and safety of the design. CFD is now commonly used to know the static and dynamic stability characteristics of complex geometries. This study aims to develop a high fidelity validation test case on modern complex geometry. For this purpose, Stability and Control Configuration (SACCON) UCAV was selected for validation purpose because of wide range of experimental data available for this configuration. The numerical study is conducted to validate the experimental results of SACCON UCAV through CFD using different turbulence models. The analysis is performed in both pitch and roll direction in order to find the stability derivatives at different angles of attack at 1 Hz frequency. Similarly, parametric analysis is performed on SACCON UCAV at single angle of attack to check the effects of Mach Number and reduced frequency. It has been concluded that modern CFD techniques can be used on complex models for analyzing the aerodynamic stability characteristics. The results of the Mach Number variation for pitch and roll motion showed that the body remains stable in both subsonic and transonic regime. Varying reduced frequency in both pitch and roll motion does not affect the aerodynamic stability of SACCON UCAV.