Numerical simulation of homogeneous mixing in T-junction micromixers
Computational fluid dynamics(CFD)was used to numerically simulate passive mixing of three different types of T-junction micromixers.The relationship between the mixing index and pressure drop loss in a simple micromixer and the inlet velocity,diffusion coefficient and pipe diameter was analyzed.The effects of structural parameters on mixing in a mixer with internal components were also studied.The results show that the mixing index increases with the increase of Reynolds number,Schmidt number and Peclet number,while the pressure drop loss increases with the increase of Reynolds number and decreases with the increase of Peclet number in laminar flow state.After adding ribs and obstacles to the T-junction micromixer,the mixing index increases first and then decreases as Re increases.The longer the rib length,the larger the inner diameter of the obstacle,and the better the mixing effect.However,the corresponding pressure drop is also greater.