Owing to the enhancement of surface effects at the micro-scale, patterned grooves on a micro-channel floor remain a powerful method to induce helical flows within a pressure driven system. Although there have been a number of numerical studies on geometrical effects concerning fluid mixing within the staggered herringbone mixer, all have focused mainly on the groove angle and depth, two factors...

We give an unified formulation for deterministic and stochastic global optimization algorithms via initial and boundary value problems for different first and second order dynamic systems. The ensemble is applied to the design of a fast-micro-mixer. The aim is to optimize a given mixer shape in order to reduce its mixing time. The algorithms are compared from their complexity and optimization e...

In this paper the influence of two different sizes of silica particles (micro-silica and nano-silica) was studied on mechanical properties of sulfur and sulfur composite. To improve the structural properties, sulfur was plasticized using dicyclopentadiene (DCPD) and methyl styrene (MSt). Plasticized sulfur composite was prepared by melt blending of plasticized sulfur and silica particles. T...

We report the development of a micromachined magnetic-bar micromixer for microscale fluid mixing in biological laboratory-on-a-chip applications. The mixer design is inspired by large scale magnetic bar mixers. A rotating magnetic field causes a single magnetic bar or an array of them to rotate rapidly within a fluid environment. A fabrication process of the magnetic bar mixer is developed. Res...

A theoretical and experimental study was performed on convective micro mixing in T-shaped micro mixers. In these devices symmetric laminar vortices are developing at low Reynolds numbers Re. The symmetry breaks up with increasing Re numbers. This leads to an enormous enhancement of the mass transfer in the mixing channel. Numerical simulations of the flow characteristics and mixing behaviour ar...

Flows in a microchannel are laminar, which means that mixing depends on only inter-diffusion. A micromixer plays an important role in obtaining fast diagnosis results in the fields of m-TAS (total analysis system), Bio-MEMS and LOC (lab-on-a-chip). In this paper, we propose a new active mixer with vertical flow placement via a series of inlets for micromixing. This has two inlets on the same ax...

The performance of micro-mixers is evaluated in terms of deviations from perfectly mixed state and mixing length (i.e., device length required to achieve perfect mixing). Different variations of T-mixer are reported for improved mixing performance, including geometric constrictions/obstacles embedded in the channel wall, heterogeneously charged walls, grooves on channel base, etc. Most of the r...

Dielectrophoretic (DEP) force, generated by interdigitated electrodes (IDEs), has been utilized to capture bio-particles for microfluidic concentration. However, due to the localized DEP force, DEP-based A -concentrators usually have shallow channels and thus are operated under low flow rates. In this thesis, we propose a mixer-enhanced DEPbased concentrator which can be operate under high flow...