Numerical schemes and hybrid approach for simulation of unsteady turbulent flows

The investigations presented a brief review of computational approaches to the modeling of turbulent flows. The paper shows that it is necessary to use eddy-resolving approaches and numerical schemes should be stable and correctly describe the evolution of vortices for the correct calculation of large-scale vortex structures. Analysis of stability and numerical diffusion of differencing schemes implemented in OpenFOAM software package has been carried out. Currently the schemes in the OpenFOAM package are not suitable for the correct calculation of the propagation and dissipation of vortices. Based on the obtained results, numerical schemes are selected and their modification has been done. The algorithm for combining URANS and LES approaches for modelling turbulent flows by means of zonal isolation of the computational domain is carried out. Validation of the implemented approach has been performed by a series of calculations of threedimensional flow around a maneuverable aircraft considering airbrake deflection. The structures of flow field around the aircraft and its aerodynamic characteristics are obtained. A comparison with the experimental data has been done.