ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Computation analyses of aeroelastic loads of rotor based on CFD/CSD coupling method
Received date: 2016-09-08
Revised date: 2016-11-09
Online published: 2016-11-27
Supported by
National Natural Science Foundation of China (11572156);A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
In order to improve the prediction accuracy of the unsteady aeroelastic load of the rotor in forward flight of the helicopter, the rotor CFD module is introduced into the comprehensive analysis method for rotor aeroelastic, and then an analytical model and corresponding code based on CFD/CSD loose coupling method are established. In order to solve the deformation problem of blade body-fitted grid caused by aeroelastic deflections such as flapping and torsional motion in rotor CFD/CSD coupling process, the blade grids are deformed using algebraic method, and blade motion deformation and rotor aerodynamic force information are transferred through the interface between fluid and solid. In the analysis method for rotor flowfield, the Navier-Stokes equations coupled with S-A turbulence model are used as governing equations, and then the rotor moving-embedded grids are constructed. The Roe scheme is employed in spatial discretization, and a dual-time algorithm is adopted for temporal discretization. In the analysis of the rotor structure, considering the rotor trim, the nonlinear equations for motion of elastic rotor are solved based on Hamilton variational principle and 20 degree of freedom Timoshenko beam model. The CSD and CFD methods are validated. Based on aforementioned work, the aeroelastic loads on the SA349/2 rotor blade, mainly including unsteady aerodynamic loads and moment in flapping, lagging and torsion direction, are calculated and compared with flight test data. Comparisons of the CFD/CSD calculated results with flight test data demonstrate that the CFD/CSD coupling method has high accuracy in calculating the rotor unsteady aerodynamic load and structural load, and can capture the peak of pressure and shock position accurately. The method proposed could be effectively applied to prediction analysis of the aeroelastic loads of the rotor.
MA Li , ZHAO Qijun , ZHAO Mengmeng , WANG Bo . Computation analyses of aeroelastic loads of rotor based on CFD/CSD coupling method[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2017 , 38(6) : 120762 -120762 . DOI: 10.7527/S1000-6893.2016.0292
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