Optimal design of groove shape on passive micromixer using design of experiment technique

Passive micromixers are one of the parts used for the mixing of two or more fluids in micro-electro-mechanical system devices, and they have been developed for various types. Fluid mixing in microscale devices is essential in microfluidic applications; however, it is difficult to mix fluids in microchannels due to the slowness of the molecular diffusion process at the microscale. In this study, optimization of the groove shape geometries of a micromixer using response surface design was performed, and the mixing performance was investigated through a numerical analysis applied with the passive scalar method. The most useful parameters were determined to be the geometric parameters of optimization, such as groove depth, groove length, distance between grooves, and groove angle. Response surface design, a design of experiments technique, was applied to the optimization procedure. The mixing index and pressure drop are important factors for evaluating the micromixer performance. Through the response surface design, this study aims to affect the groove shape of a passive micromixer. Consequently, it was concluded that the groove length and distance between grooves improved the mixing performance and decreased the pressure drop. In addition, optimal models were proposed for the passive micromixer.