The fly-wing configuration with low aspect ratio has better stealth and aerodynamic performance, and therefore, is the advanced configuration of future fighter. In CFD simulation of fly-wing aircraft, the full wing design makes it difficult to generate high quality body-fitted grids. In contrast, adaptive Cartesian grid method has the advantages of automation and high quality. In this paper, the adaptive Cartesian grid technology is developed, and the numerical simulation of fly-wing configuration with low aspect ratio is carried out. Firstly, combining the improved method of determining the grid cell type with the adaptive method based on the geometric characteristics and flow field solution characteristics, a highly efficient, robust and high-quality three-dimensional adaptive Cartesian mesh generation technology is developed by using the fully threaded tree Cartesian mesh data structure and optimizing the near wall mesh through the virtual layer technology. For the processing of non-body-fitted wall boundary, the basic method is developed based on the ghost cell reconstruction technique of immersed boundary method, and the high fidelity boundary conditions of non-body-fitted Cartesian grids are constructed. For viscous flow control equations, the numerical discretization method in the framework of Cartesian grids is developed, and the numerical solver of Navier-Stokes equations suitable for adaptive Cartesian grids is established. Based on the above work, the application of adaptive Cartesian grid technique is carried out. The application research of fly-wing configuration with low aspect ratio in low-speed flow problem proves the reliability of the technical method developed in this paper, and deeply explores the influence of adaptive technology on flow field characteristics and aerodynamic characteristics.
CHEN Hao
,
HUA Ruhao
,
YUAN Xianxu
,
TANG Zhigong
,
BI Lin
. Simulation of flow around fly-wing configuration based on adaptive Cartesian grid[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2022
, 43(8)
: 125674
-125674
.
DOI: 10.7527/S1000-6893.2021.25674
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