Influence of structural elasticity on the aerodynamic characteristics of the common research model with deflected control surfaces

Abstract

Numerical aerodynamic and aeroelastic investigations are conducted for the Common Research Model (CRM) configuration with deployable aileron control surfaces and a trimmable horizontal stabilizer at cruise and off-cruise conditions. The numerical methodology which is implemented in the multi-disciplinary simulation environment SimServer is based on CFD and coupled CFD-CSM simulations. The DLR Tau Code is applied in order to solve the Reynolds-Averaged-Navier-Stokes (RANS) equations. The Spalart-Allmaras turbulence model with Edwards modification is used for the closure modeling of the three-dimensional RANS equations. A linear modal solver is utilized to calculate structural displacements and rotations of control surfaces are modeled by a Chimera approach. A grid independence study is conducted by using the rigid aerodynamic model of the CRM. The main focus of the analysis lies on the evaluation of the stationary CFD-CSM simulations addressing the influence of structural deformation on aileron effectiveness. Influences of various flow conditions and different fuel tank filling levels on the resulting local and global aerodynamic properties of the CRM are investigated. The reduction of aileron effectiveness as well as the difference in horizontal trim deflection angle if structural elastic effects are considered is investigated for the considered Mach number range and aircraft mass configurations.