To gain high efficiency for the simulation of the aerodynamic characteristics of the rotor in hover,body?fitted momentum source(BFMS)method is proposed.In this method,the actual blade geometry is represented by the si...To gain high efficiency for the simulation of the aerodynamic characteristics of the rotor in hover,body?fitted momentum source(BFMS)method is proposed.In this method,the actual blade geometry is represented by the single layer of volume grid surrounding the blade.Aiming at correctly simulating the aerodynamic characteristics of the discrete cells along the chordwise of blade airfoil section,a new distributed force model is proposed.For comparison,the RANS method with S?A turbulence model and the steady rotor momentum source(SRMS)method based on embedded grid systems are established,respectively.And the grid connecting methodology is improved to embed the blade into the background grids for the three methods.Then,simulations are performed for the hovering Caradonna?Tung rotor by these methods,and the calculated results are compared with the available experimental data.Moreover,the pressure distributions along the blade are compared with the conventional momentum source methods.It is demonstrated that the BFMS method can be employed as an effective approach to predict rotor aerodynamic characteristics with a low computational resource and reasonable accuracy.展开更多
A rotor CFD solver is developed for simulating the aerodynamic interaction phenomenon among rotor, wing and fuselage of a tilt rotor aircraft in its helicopter mode. The unsteady Navier-Stokes equations are discretize...A rotor CFD solver is developed for simulating the aerodynamic interaction phenomenon among rotor, wing and fuselage of a tilt rotor aircraft in its helicopter mode. The unsteady Navier-Stokes equations are discretized in inertial frame and embedded grid system is adopted for describing the relative motion among blades and nacelle/wing/fuselage. A combination of multi-layer embedded grid and 'extended hole fringe' technique is complemented in original grid system to tackle grid assembly difficulties arising from the narrow space among different aerodynamic components, and to improve the interpolation precision by decreasing the cell volume discrepancy among different grid blocks. An overall donor cell searching and automatic hole cutting technique is used for grid assembly, and the solution processes are speeded up by introduction of OpenMP parallel method. Based on this solver, flow fields and aerodynamics of a tilt rotor aircraft in hover are simulated with several rotor collective angles, and the corresponding states of an isolated rotor and rotor/wing/fuselage model are also computed to obtain reference solution. Aerodynamic interference influences among the rotor and wing/fuselage/nacelle are analyzed, and some meaningful conclusions are drawn. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.展开更多
基金supported by the Qian Xuesen Innovation Foud of China Aerospace Science and Technolygy Corporation
文摘To gain high efficiency for the simulation of the aerodynamic characteristics of the rotor in hover,body?fitted momentum source(BFMS)method is proposed.In this method,the actual blade geometry is represented by the single layer of volume grid surrounding the blade.Aiming at correctly simulating the aerodynamic characteristics of the discrete cells along the chordwise of blade airfoil section,a new distributed force model is proposed.For comparison,the RANS method with S?A turbulence model and the steady rotor momentum source(SRMS)method based on embedded grid systems are established,respectively.And the grid connecting methodology is improved to embed the blade into the background grids for the three methods.Then,simulations are performed for the hovering Caradonna?Tung rotor by these methods,and the calculated results are compared with the available experimental data.Moreover,the pressure distributions along the blade are compared with the conventional momentum source methods.It is demonstrated that the BFMS method can be employed as an effective approach to predict rotor aerodynamic characteristics with a low computational resource and reasonable accuracy.
文摘A rotor CFD solver is developed for simulating the aerodynamic interaction phenomenon among rotor, wing and fuselage of a tilt rotor aircraft in its helicopter mode. The unsteady Navier-Stokes equations are discretized in inertial frame and embedded grid system is adopted for describing the relative motion among blades and nacelle/wing/fuselage. A combination of multi-layer embedded grid and 'extended hole fringe' technique is complemented in original grid system to tackle grid assembly difficulties arising from the narrow space among different aerodynamic components, and to improve the interpolation precision by decreasing the cell volume discrepancy among different grid blocks. An overall donor cell searching and automatic hole cutting technique is used for grid assembly, and the solution processes are speeded up by introduction of OpenMP parallel method. Based on this solver, flow fields and aerodynamics of a tilt rotor aircraft in hover are simulated with several rotor collective angles, and the corresponding states of an isolated rotor and rotor/wing/fuselage model are also computed to obtain reference solution. Aerodynamic interference influences among the rotor and wing/fuselage/nacelle are analyzed, and some meaningful conclusions are drawn. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.
