TY - JOUR N2 - The numerical investigation of the mixing process in complex geometry micromixers, as a function of various inlet conditions and various micromixer vibrations, was performed. The examined devices were two-dimensional (2D) and three-dimensional (3D) types of serpentine micromixers with two inlets. Entering fluids were perturbed with a wide range of the frequency (0 - 50 Hz) of pulsations. Additionally, mixing fluids also entered in the same or opposite phase of pulsations. The performed numerical calculations were 3D to capture the proximity of all the walls, which has a substantial influence on microchannel flow. The geometry of the 3D type serpentine micromixer corresponded to the physically existing device, characterised by excellent mixing properties but also a challenging production process (Malecha et al., 2009). It was shown that low-frequency perturbations could improve the average mixing efficiency of the 2D micromixer by only about 2% and additionally led to a disadvantageously non-uniform mixture quality in time. It was also shown that high-frequency mixing could level these fluctuations and more significantly improve the mixing quality. In the second part of the paper a faster and simplified method of evaluation of mixing quality was introduced. This method was based on calculating the length of the contact interface between mixing fluids. It was used to evaluate the 2D type serpentine micromixer performance under various types of vibrations and under a wide range of vibration frequencies. L1 - http://www.journals.pan.pl/Content/84986/PDF/09-paper-Malecha.pdf L2 - http://www.journals.pan.pl/Content/84986 PY - 2014 IS - No 3 September EP - 385 DO - 10.2478/cpe-2014-0028 KW - Serpentine micromixer KW - active mixing KW - numerical simulations KW - LTCC technology A1 - Malecha, Ziemowit M. A1 - Malecha, Karol PB - Polish Academy of Sciences Committee of Chemical and Process Engineering DA - 2014 T1 - Numerical Analysis Of Mixing Under Low And High Frequency Pulsations At Serpentine Micromixers SP - 369 UR - http://www.journals.pan.pl/dlibra/publication/edition/84986 T2 - Chemical and Process Engineering ER -