The stainless steel bipolar plate has received much attention due to the cost of graphite bipolar plates. Since the micro-channel of bipolar plates plays the role of fuel flow field, electric connector and fuel sealing, an investigation of the deep drawing process for stainless steel micro-channel arrays is reported in this work. The updated Lagrangian formulation, degenerated shell finite elem...

In this study, high-fidelity conjugate heat transfer simulations are used to model a micro-channel exchanger (MCHE) in crossflow study its thermal-hydraulic performance. Three different microchannel geometries, namely circular, triangular, and square with louver-shaped fins, considered. The local flow field showed strong coupling between the flow, solid domain, crossflow. separation wake region...

We introduce a method to enhance the luminescence of GaN-based LEDs by combining the direct heteroepitaxy laterally overgrowth (DHELO) technique with selective wet etching process. The epitaxial overgrowth of GaN layers on sapphire substrate with SiO2 micro-rods array exhibited a reduced dislocation density and improved the crystal quality. The EL intensity of LEDs with SiO2 micro-rods array wa...

(1) Background: Microfluidic chips have found extensive applications in multiple fields due to their excellent analytical performance. As an important platform for micro-mixing, the performance of micromixers has a significant impact on analysis accuracy and rate. However, existing with high mixing efficiency are accompanied by pressure drop, which is not conducive integration micro-reaction sy...

With the introduction of antenna array systems into wireless communication networks comes the need to better understand the spatial characteristics of the channel. Scattering models provide both angle of arrival (AOA) and time of arrival (TOA) statistics of the channel. A number of different scattering models have been proposed in the literature including elliptical and circular models. These m...

The trend to miniaturization cannot be overseen. The use of very small electronic and electro-optical components in a variety of consumer and investment goods is leading to an increasing demand for small-scale servo actuators for micro assembly applications in production equipment. The previous generation of micro gears and micro actuators was not suited to this type of application, because of ...

The analysis of capillary waves in confined microspace by quasi-elastic laser scattering (QELS) method enables surface tension measurements. In contrast to previous works, a simple single-beam-focusing method based on spontaneous capillary wave resonance with its confined size is proposed. The capillary wave resonance has been successfully demonstrated in confined two-dimensional micro surface ...

Cesium chloride centrifugation of DNA extracted from cells of blood strain Trypanosoma lewisi revealed a main band, rho = 1.707, a light satellite, rho = 1.699, and a heavy satellite, rho = 1.721. Culture strain T. lewisi DNA comprised only a main band, rho = 1.711, and a light satellite, rho = 1.699. DNA isolated from DNase-treated kinetoplast fractions of both the blood and culture strains co...

Title of Dissertation: STUDY OF CONDENSATION OF REFRIGERANTS IN MICRO-CHANNELS FOR DEVELOPMENT OF FUTURE COMPACT MICRO-CHANNEL CONDENSERS Sourav Chowdhury, Doctor of Philosophy, 2008 Directed By: Professor Michael Ohadi, Department of Mechanical Engineering Miniand microchannel technology has gained considerable ground in the recent years in industry and is favored due to its several advantages...

This study examines the single-phase and two-phase cooling performance of a hybrid micro-channel/micro-jet impingement cooling scheme using HFE 7100 as working fluid. This scheme consists of supplying coolant from a series of jets that deposit liquid into the micro-channels. A single-phase numerical scheme that utilizes the k–e turbulent model and a method for determining the extent of the lami...