Flutter-enhanced mixing in small-scale mixers

Enhancement of mixing via flow-induced flutter of a flexible membrane is explored for small-scale mixers that operate at low Reynolds numbers. Flow induced flutter and mixing in a duct flow is simulated using fully coupled fluid-structure-scalar interaction simulations including two-way coupling between the fluid and structure. The fluid and structural dynamics are analyzed and their impact on the mixing performance is characterized. The sensitivity of the system to the Reynolds number and to the membrane’s size and shape are also examined. It is shown that these flutter mixers create complex vortex structures even at low Reynolds numbers and these vortex structures lead to complex stretching and folding of fluid interfaces resulting in rapid mixing.