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Transport Phenomena Commons™

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2005

Articles 1 - 4 of 4

Full-Text Articles in Transport Phenomena

Stability Of Transport And Rate Processes [Review], Yaşar Demirel Jun 2005

Stability Of Transport And Rate Processes [Review], Yaşar Demirel

Papers in Thermal Mechanics

About fifty years ago, the Turing instability demonstrated that even simple reaction-diffusion systems might lead to spatial order and differentiation, while the Rayleigh-Bénard instability showed that the maintenance of nonequilibrium might be the source of order in fluids subjected to a thermodynamic force above a critical value. Therefore, distance from global equilibrium in the form of magnitude of a thermodynamic force emerges as another constraint of stability; some systems may enhance perturbations, and evolve to highly organized states called the dissipative structures after a critical distance on the thermodynamic branch. Although the kinetics and transport coefficients represent short-range interactions, chemical …

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Transport Analysis And Model For The Performance Of An Ultrasonically Enhanced Filtration Process, Michael T. Grossner, Joanne M. Belovich, Donald L. Feke Jun 2005

Transport Analysis And Model For The Performance Of An Ultrasonically Enhanced Filtration Process, Michael T. Grossner, Joanne M. Belovich, Donald L. Feke

Chemical & Biomedical Engineering Faculty Publications

This paper presents an analysis of a filtration technique that uses ultrasound to aid the collection of small particles (tens of microns in diameter) from suspension. In this method, particles are retained within a porous mesh that is subjected to a resonant ultrasonic field, even though the pore size of the mesh is two orders of magnitude greater than the particle diameter. The role of acoustic forces in driving the retention phenomena has previously been studied on a micro-scale, which included modeling and experimental verification of particle motion and trapping near a single element of the mesh. Here, we build …

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Blood Flow Measurements With Magnetic Resonance Phase Velocity Mapping, George P. Chatzimavroudis Apr 2005

Blood Flow Measurements With Magnetic Resonance Phase Velocity Mapping, George P. Chatzimavroudis

Chemical & Biomedical Engineering Faculty Publications

Magnetic resonance (MR) phase velocity mapping (PVM) is a non-invasive technique that can measure the flow velocity in any spatial direction in an imaging slice. This technique has wide application in the clinical field in quantifying blood flow, as well as in non-biomedical areas. This review describes the value and/or potential of MR PVM as a diagnostic/monitoring technique in heart valve regurgitation and in the total cavo-pulmonary connection. A single slice placed in the aortic root can accurately quantify the aortic regurgitant volume. A multi-slice control volume method has high potential for the quantification of the mitral regurgitant volume. …

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Transient Analysis Of A Porous Electrode, Sheba Devan, Venkat R. Subramanian, Ralph E. White Jan 2005

Transient Analysis Of A Porous Electrode, Sheba Devan, Venkat R. Subramanian, Ralph E. White

Faculty Publications

An analytical expression is presented for the voltage response including the transient voltage for a simple (i.e., no concentration gradients) porous electrode model subject to a sinusoidal input current density. The transient voltage response as a function of the frequency, exchange current density, and double layer capacitance is studied independent of the periodic (steady state) voltage response. The change in the voltage response in the transient region is compared to that of the periodic voltage response with respect to the parameters. The physical properties of the porous electrode can be estimated using the voltage response in the transient …

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