Performance of microball micromixers using a programmable magnetic system by applying novel movement patterns

The rapid achievement of a desirable mixing level at microscales is one of the most challenging aspects of microfluidic systems, whereby micromixers could open the door to efficient mixing on lab -on -a -chip platforms. Although a wide range of strategies have been explored in active and passive micromixers to improve the mixing, the ability to optionally control the mixing is a key factor that is often overlooked. Hereupon, in this study, the adjustable mixing in a novel 3D -printed micromixer by analyzing the effect of various movement patterns of an actuator is examined. In this micromixer, a stainless steel microball is driven as an actuator using a programmable magnetic system. Initially, with the continuous and non -continuous revolving of the microball, the mixing index in these movement patterns are evaluated. The results show that the mixing index in the proposed micromixer reaches as high as 90% for Reynolds number of 5 by the pendular motion of the microball. Eventually, the main mixing zone of this micromixer is developed by adding inlet and outlet mixing zones, each containing a microball. This on -demand micromixer can pave the way for chemical and biological applications under various operating conditions in a wide range of Reynolds numbers.