In this master thesis the results of turbulent flow simulations in pipe with a bend are presented. Simulations were conducted using OpenFOAM, a code for computational fluid dynamics. We conducted large eddy simulation, however basic idea of direct numerical simulation is also presented. We simulated flows with different Reynolds numbers, namely with 1400, 5600 and 10000. We assumed incompressible flow of Newtonian fluid. We used different computational meshes for flows with different Reynolds number. Quality of meshes and accuracy of simulations was checked by comparing one dimensional profile results from our simulations with results from direct numerical simulations. We were especially interested in effect of the pipe bend on simmetry of the flow after the bend. For that reason we introduced a velocity asymmetry parameter, which we calculated for all considered flows. We compared asymmetry parameter dependency along the pipe for all flows. The same comparison was performed for the velocity fluctuations. We also compared fluctuations asymmetry parameter dependency along pipe for all flows. We then evaluated asymmetry of the flow with introduction of asymmetry parameters of wall shear stress and vorticity magnitude. Lastly we compared results of different parameters.
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