Numerical simulation of flow around an immersed cylinder in turbulence generated by a network of upstream cylinders.

Authors

1 arak university of technology

2 Arak university of technology

10.22044/jsfm.2025.16124.3966

Abstract

This study aims to investigate the effect of incoming flow turbulence around a circular cylinder. To generate turbulence, an array of upstream circular cylinders was modeled, and its influence on the flow behavior around the main cylinder was analyzed. The flow was simulated using a two-dimensional, transient approach with the commercial software ANSYS Fluent, employing the k-ω SST turbulence model at a Reynolds number of 22,000. For validation, the results of the present study were compared with those of previous research, showing good agreement. The findings indicate that when the distance between the turbulence-generating cylinders and the main cylinder is 6D, the highest level of vortex interaction occurs, increasing the turbulence intensity around the main cylinder up to 0.9. Evaluation of the drag and lift coefficients shows that the drag coefficient decreases by approximately 76%, and the lift coefficient increases by nearly 13 times compared to the base case. These validated results highlight the potential of passive turbulence-generating arrays for flow control in bluff body applications and offer insight into drag reduction and mitigation of vortex-induced vibrations.

Keywords

Main Subjects


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