# Direct numerical simulation of turbulent flow around an impulsively started circular cylinder by using mesh-free vortex method

 International Journal of Mechanical Engineering © 2015 by SSRG - IJME Journal Volume 2 Issue 11 Year of Publication : 2015 Authors : Amirreza Mohammadian, Suresh Akella, A.M.K Prasad 10.14445/23488360/IJME-V2I11P103
##### How to Cite?

Amirreza Mohammadian, Suresh Akella, A.M.K Prasad, "Direct numerical simulation of turbulent flow around an impulsively started circular cylinder by using mesh-free vortex method," SSRG International Journal of Mechanical Engineering, vol. 2,  no. 11, pp. 13-18, 2015. Crossref, https://doi.org/10.14445/23488360/IJME-V2I11P103

##### Abstract:

Direct numerical simulation of turbulent flow, wake flow, using the random vortex method involving vortex blobs is presented and implemented in this paper. The method is used to perform highresolution simulations of incompressible twodimensional, Navier-Stokes fluid flows. In the random vortex method, vorticity of the flow field is the primary variable. After generation on the cylinder wall, it is followed in two separate fractional time step in a Lagrangian approach, namely convection and diffusion. In this paper, the developed random vortex method applied to the flow past one impulsively started circular cylinder. the flow simulations are carried out in the high Reynolds number Re=140000. Instantaneous velocity vector field and Instantaneous velocity and position of each vortex element in the flow at same time are plotted. The code has been validated by using experimental data to demonstrate accuracy of produced solution without the effects of grid-based numerical diffusion.

##### Keywords:

Turbulence, Vortex, Random vortex, mesh-free, Vorticity.

##### References:

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