| The modern advanced combat aircrafts, not only are designed to meet the demand for increased speed, but also call for higher maneuverability at high angles of attack beyond post-stall conditions. Delta wing layout can well meet the requirements in different range of fight speed. So it is necessary to launch study on numerical simulation of delta wing at high angle of attack.In the paper, study of the flow field of flow around a cylinder and delta wing at high angles of attack are carried out using OpenFOAM. First numerical simulations of flow around a cylinder are carried out using SA-DDES model. The drag coefficient and Strouhal number calculated by the numerical simulation of flow around a cylinder under different Reynolds number have a good consistency with the other references results, which verifies the feasibility of OpenFOAM software.Then calculation of the 60 deg delta wing with bracket flow field at angles of attack of 0 deg,10 deg,30deg,50deg,70deg,90deg, are carried out using SA model and SA-DDES model. The computational aerodynamic parameters under different angles of attack are compared with experimental data, the results show that:before vortex breakdown, aerodynamic parameters are calculated using SA model and SA-DDES model have a good consistency with the experimental data, but after vortex breakdown, SA model showed a significant deficiencies, and SA-DDES you can get better results.Finally, in order to study the impact of the bracket on the delta wing aerodynamic characteristics and flow field, using SA-DDES model calculates delta without bracket flow field. The results show that:compared with the situation with bracket, computational normal force coefficient is smaller. The results also showed that bracket have some impacts on the flow field near the wing. When the angle of attack is small, the bracket has little impact on the flow field near the wing. But as the angle of attack increases, the impact of the bracket will become strong on flow field. |
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