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Prediction of the Pressure Drop Through Micromachined Particle Filters

Yang J.M., Yang X., Yang J.M., Yang X., Ho C-M., Tai Y-C., UCLA, US

Micro-filters are fabricated using MEMS technology, and both measurements and numerical calculations are carried out in order to estimate the power requirement in a micron-size particle collection process using the micro-filter. In order to numerically [...]

Computer Simulations of Electrokinetic Mass Transport in Microfabricated Fluidic Devices

Ermakov S.V., Jacobson S.C., Ramsey J.M., Oak Ridge National Laboratory, US

A mathematical model and computer code for simulat-ing electrokinetic fluid and sample manipulations in micro-fabricated fluidic devices (microchips) are described. The model accounts for mass transport mechanisms such as electrophoretic migration, bulk fluid motion due [...]

Stability Criterion for Microscale Concentric Flow of Two Immiscible Liquids

Ho L.W., Marchetti J., Gallegos C., IntelliSense Corporation, US

This paper addresses the establishment of a stability criterion for isothermal laminar concentric flow of two immiscible liquids. Using the approach of combined non-dimensional group anlysis and numerical simulations, it is established that the inner [...]

A Passive Fluid Valve Element for a High-Density Chemical Synthesis Machine

Moroney R.M., Amantea R., McBride S.E., Sarnoff Corporation, US

We have developed a passive valve element for use in a high-density chemical synthesis machine. The element stops fluid flow by the surface tension forces occurring at small channel openings. The openings are circular holes [...]

Simulation of Electroosmosis Using a Meshless Finite Point Method

Mitchell M.J., Aluru N.R., University of Illinois, US

A Finite Point Method (FPM) based on a weighted least squares interpolation is presented for the simulation of electroosmotic transport in capillaries. This method requires no mesh and involves no Galerkin-type integration, making it more [...]

A Fast 3D Solver for Unsteady Stokes Flow with Applications to Micro-Electro-Mechanical Systems

Ye W., Kanapka J., White J.K., Massachusetts Institute of Technology, US

In this paper we describe the extensions made to FastStokes, a precorrected-FFT accelerated stady Stokes solver, to solve the unsteady Stokes equation. We demonstrate the accuracy of the numerical approach by comparing computed results to [...]

Lubrication Analysis and Boundary Integral Simulations of a Viscous Micropump

Day R.F., Stone H.A., Harvard University, US

Several recent papers discuss a novel viscous micropump consisting of Poiseuille flow of fluid between two plates and a cylinder placed along the gap perpendicular to the ow direction. If the cylinder is not centered, [...]

Scaling Issues for Calculations of Low-Velocity Gaseous Microflows

Kaplan C.R., Oran E.S., Naval Research Laboratory, US

Gaseous flows in microfluidic devices are often characterized by relatively high Knudsen numbers, Kn. For such flows, the continuum approximation is not valid, and Direct Simulation Monte Carlo (DSMC) is an appropriate solution method. However, [...]

Efficiency and Accuracy Improvements for FastStokes, A Precorrected-FFT Accelerated 3-D Stokes Solver

Ye W., Kanapka J., Wang X., White J.K., Massachusetts Institute of Technology, US

In this paper we present several efficiency and accuracy improvement to the precorrected-FFT accelerated Stokes flow solver, FastStokes. Accuracy was improved by deriving analytical formulas for required integrals of Stokes equation Green sfunctions, cpu time [...]

Inductive Fault Analysis of a Microresonator

Jiang T., Kellon C., Blanton R.D., Carnegie Mellon University, US

We study the failure mechanisms of a microresonator. A MEMs process simulation tool is used to discover the full spectrum of defective structures caused by particulate contaminations introduced during manufacturing. Based on process simulation results, [...]