APPLICATION OF COMPUTATIONAL FLUID DYNAMICS IN AERONAUTICS

Mirko Kozić

Abstract:

The monograph consists of three parts. Theoretical basics of two concepts with significant roles in the generation of stable schemes of computational fluid dynamics are presented in the first part. One concept relates to weak solutions of the Euler equations, whose integral form enables obtaining flow field discontinuities as a part of the solution. The second concept is characteristic surfaces that determine the main flow structure, zones of influence and dependence. The second part includes numerical meshes as inseparable part of computational fluid dynamics. The basics types of the numerical meshes and their main features are presented.  Special attention is paid to deformable grids that entirely follow motion and deformation of a body in the unsteady flow field. In the third part, results of the numerical flow dynamics are shown. First, results obtained by solving the unsteady two-dimensional Euler equations applied to airfoil rotation, control surface deflection and airfoil translation are given, followed by the results of application of commercial software ANSYS FLUENT in solving the steady and transient averaged Navier-Stokes equations. The previously mentioned software was used in modelling the flow in two-dimensional nozzle with obstacle at the exit, serving for thrust force directing, determining the flow field around the tunnel model of the LASTA-95 airplane at an angle of attack corresponding the moderately steep spin and modelling of flow around Mi-8 helicopter in translatory flight.

Key words: aeronautics, computational fluid dynamics, flow equations, Euler equations, Navier-Stokes equations, airplane, nozzle, helicopter, spin