Numerical Studies of Curved-walled Micro Nozzle/Diffuser

In this study, commercially available software CFD was adopted for analyzing the performance of straight-walled and curved-walled micro nozzle/diffuser. Such nozzle/diffuser was used in valve-less micro-pumps. This model tested different types of nozzle/diffuser and the results showed that the pressure loss coefficient for nozzle/diffuser decreases with the increase of Reynolds number. At the same Reynolds number, the pressure loss coefficient for nozzle is higher than that of the diffuser. At a given volumetric flow rate, the pressure loss coefficient and ratio of pressure loss coefficient for curved-walled nozzle/diffuser are slightly higher than that of the straight-walled nozzle/diffuser. In this study, the numerical data was found good agreement with previous analytic solution and experimental results.