Numerical assessment on liquid mixing in a T-mixer containing tri-fin

Liquid mixing in channel with laminar uniaxial flow is inefficient, and the mixing channel length required for diffusive mixing is immensely large. In the attempt to enhance liquid mixing, this study presents computational evaluation of mixing performance of tri-fin configuration in a T-mixer. Two parameters, that is, transverse spacing (S-T) and width (L-w) of the upstream fin, are studied to evaluate the geometrical scaling effect of the tri-fin configuration. It is shown that tri-fin unit with S-T/H = 0.2 and L-w/H = 0.2 yields superior overall mixing performance, amongst the geometrical parameters investigated. For flow at low Reynolds number (Re <= 1), 20 periodic units of tri-fin are sufficient to achieve maximum enhancement with 29% reduction of mixing efficiency length L-M = 99%. It is also shown that there exists a progressive mixing enhancement with increasing number of tri-fin periodic units employed. Taking into consideration of the pumping power limitation, it would be ideal to employ tri-fin feature to improve liquid mixing for fluids with high Schmidt number, flowing at low Reynolds number.