CFD simulation of fractal-shaped orifices for flow measurementimprovement

• Fractal shaped orifice has significant effects on the flow mixing properties downstream a pipe due to their edge self-similarity.
• Simulation results are in a good agreement with that obtained from published experimental results.
• Fractal shaped orifice has effect on pressure drop and is lower than of ordinary orifice by around 1.25%.
• Simulation results showed that as the fractal iterations increase, better effect on the flow mixing and flow recovery is achieved.
• Results showed that velocity scales developed by the fractal orifices is broader than that of ordinary orifice.

The effect of using fractal-shaped orifice as flow meters for enhancing flow measuring techniques and their effect on pressure drop and flow mixing properties from point of view of losses saving and future designing of measuring devices with higher accuracy has been investigated.In this frame, a numerical simulation has been used to study a turbulent flow through fractal-shaped orifices in pipes. Different fractal-shaped orifices; namely GEN-1, GEN-2, GEN-3 and GEN-4, have been constructed up to the forth iteration using a commercial CFD package. The studied pipe has a diameter of 0.14 m and a total length of 2.5 m.To validate the numerical simulation results, a direct comparison has been made with recently published experimental results for fractal-shaped orifice to illustrate the effect of the fractal-shaped on the pressure drop.Numerical results showed that the fractal shaped orifice has a significant effect on the flow mixing properties and on the pressure drop downstream a pipe owing to their edge self-similarity shapes.