ACTA AERONAUTICAET ASTRONAUTICA SINICA >
High-resolution numerical research on formation and evolution mechanism of rotor blade tip vortex
Received date: 2016-10-13
Revised date: 2016-12-14
Online published: 2017-02-06
Supported by
National Natural Science Foundation of China (11302103);Funding of Jiangsu Innovation Program for Graduate Education (KYLX15_0238);The Fundamental Research Funds for the Central Universities
To capture the formation and evolution process of the helicopter blade tip vortex in detail, a computational fluid dynamics (CFD) method based on refined grids and a high-order interpolation scheme is presented. In this method, the Navier-Stokes equation in the rotating coordinate system is selected as the governing equation. For spatial discretization, the upwind Roe scheme together with a fifth-order WENO (Weighted Essentially Non-Oscillatory) scheme is employed to calculate the convective variables. A dual-time method is utilized for time marching, and the implicit LU-SGS (Lower-Upper Symmetric Gauss-Seidel) scheme is adopted for every pseudo time step. The information between blade grid and the background grid is exchanged by using the overset grid method. With the method developed, the tip vortex flowfield of a hovering rotor is simulated accurately, and the detailed formation process and the evolution of the blade tip vortex are captured in the blade and background grids, respectively. The formation and evolution mechanisms of the blade tip vortex are then discussed. It is demonstrated that the current high-accuracy method is effective in simulating the formation and evolution of the blade tip vortex in hover condition. The cross flow around the blade tip is firstly attached to the blade, and then the boundary layer grows due to the pressure gradient. With advancing downstream, the vortex core is gradually identifiable, and is detached from the tip blade ultimately.
Key words： blade tip vortex; WENO scheme; overset grid; computational fluid dynamics; rotor; helicopter
YE Zhou , XU Guohua , SHI Yongjie . High-resolution numerical research on formation and evolution mechanism of rotor blade tip vortex[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2017 , 38(7) : 520846 -520846 . DOI: 10.7527/S1000-6893.2017.120846
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