Numerical study of 3-D helical passive micromixer having both inlets at offset with blood as fluid

Abstract

In the present study, two different micromixers have been evaluated for their mixing efficiencies with non-Newtonian working fluid blood. This helical micromixer has been chosen since it solves the problem of high mixing time during the mixing of fluids at the micro-level. This helical micromixer has both of its inlets at an offset to each other and is named TDHM-TO, i.e., 3D helical micromixer with inlet at offset. When this helical micromixer was compared with standard simple T-micromixer (STM), it is found that TDHM-TO requires much less mixing length than that of STM and still provides better mixing efficiency. Continuity equation, Navier-Stokes and species transport equations have been solved to investigate the mixing efficiency of the micromixers for non-Newtonian fluid blood. The study considers a wide range of mass flow rates (0.0004 kg/hr.–0.10 kg/hr.). It is being found that, for all values of mass flow rate, TDHM-TO performed much better than STM. E.g., for flow rate = 0.07 kg/hr., TDHM-TO provide a mixing efficiency of 74.41% compared to 4.93 of STM which is about 65.2% more than that of STM. STM showed a very poor result compared to TDHM-TO with only 7.64% of maximum mixing efficiency obtained with the flow rate = 0.1 kg/hr. compared to 72.84% of TDHM-TO. This TDHM-TO micromixer can be, thus, utilized in many chemicals, biochemical, and biomedical industries because of its higher efficiency and lower mixing length.