Numerical simulation of flow through microchannels of technical equipment with triangular and rectangular elements of roughness


natural mechanical engineering, roughness, microchannels, Ansys, friction factor

How to Cite

Kmiotek, M., & Iwan, T. (2021). Numerical simulation of flow through microchannels of technical equipment with triangular and rectangular elements of roughness. Technologia I Automatyzacja Montażu (Assembly Techniques and Technologies), 114(4), 16-23. Retrieved from


This paper presents a computational study on an influence of a rough surface on the fluid flow in a microchannel used in various technical microdevices of complex products. Two-dimensional axially symmetrical microchannels with a circular cross-section were considered. The fluid flow were simulated as simple geometric figures, i.e. a triangle and a rectangle with different height h and different distance s between each other. The flow equations were solved with Ansys / Fluent software. A streamline analysis is performed to investigate the flows in the recirculation zone behind the roughness elements. It was found that the friction factor increases with increasing height of rough elements. The coefficient of friction factor is greater for rectangular elements than for triangular elements, and decreases as the geometry of the element changes. Friction factor decreases as the Reynolds number increases. The authors indicate that in the production of microchannels of complex products, it is recommended to use triangular elements to model roughness.

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