# The Discrete Vortex Method for estimating how surface roughness affects aerodynamic drag acting on a long cylinder exposed to wind

### Tomasz Nowicki

##### Abstrakt

This paper focuses on the aerodynamic drag force that acts on a long cylinder standing up to aerodynamic wind in the critical regime of the fluid flow. The core problem addressed here is how surface roughness of a high level and further increase of that level affects the drag. The research is based on computer simulations using the Discrete Vortex Method. A meshless version of the method was applied in order to let the boundary layer form freely in the way of a direct computer simulation. Fundamental ideas behind the Discrete Vortex Method, the original research program and the obtained results are presented. The main conclusion is that a small level of surface roughness may be neglected in engineering estimations.

Słowa kluczowe: wind engineering, discrete vortex method, surface roughness, aerodynamic force, aerodynamic drag
##### References

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