The MEMS Handbook Introduction & Fundamentals (2nd Ed) - M Gad el Hak Part 7 pdf

... profiles generally agree well with the DSMC results. The temperature and Mach number profiles especially show very close agreement with the DSMC 8-3 0 MEMS: Introduction and Fundamentals 0.0 1.0 2.0 ... channel, the tangential velocity component to the wall is retained, while the velocity component normal to the wall is neglected at wall boundaries in the region 0 Յ x...

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... indeterminate set of equations. The continuum model is easier to handle mathematically (and is also more familiar to most fluid dynamicists) than the alternative molecular models. Continuum mod- els ... listed in the comments columns of the tables. The question of the effect of size on the strength of MEMS materials often arises. This is because MEMS structural components ca...

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... process. The present section discusses molecular-based models and their relation to the continuum models previously considered. The most fundamental of the molecular models is deterministic. The motion ... Isotropic Fluid,” J. Fluids Eng. 1 17, pp. 3–5. Gad- el- Hak, M. (1999) The Fluid Mechanics of Microdevices: The Freeman Scholar Lecture,” J. Fluids Eng. 121, pp. 5–33. Ga...

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... LLC 5 Integrated Simulation for MEMS: Coupling Flow-Structure- Thermal-Electrical Domains 5.1 Introduction 5-1 Full-System Simulation • Computational Complexity of MEMS Flows • Coupled-Domain Problems • A ... cantilever microbeam made of piezoelectric material. The emphasis may be on modeling the electronic circuit and the motion, and thus a simple model for the motion-induced...

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... for microfluidic problems. Molecular-Based Microfluidic Simulation Models 6-1 9 © 2006 by Taylor & Francis Group, LLC 7- 1 7 Hydrodynamics of Small-Scale Internal Gaseous Flows 7. 1 Introduction 7- 1 Overview ... of the Navier–Stokes equations, as well as the molecular interaction models of the MD and the DSMC methods. Although it may seem that the molecular simulatio...

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... (2002) “Molecular-Based Microfluidic Simulation Models,” in Handbook of MEMS, 1st ed., M. Gad- el- Hak, ed., CRC press, Boca Raton. Bird, G.A. (1994) Molecular Gas Dynamics and the Direct Simulation ... on the molecular distribution function of the surrounding gas, the ther- mophoretic force can be calculated by integrating the momentum flux imparted by the molecules strik-...

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... Taylor & Francis Group, LLC 1 1-2 MEMS: Introduction and Fundamentals attention of MEMS researchers since the early days of MEMS development, and there have been several demonstrations of micromotors ... gradients in the microchannel. Probably the most common cause of this is a mis- match in the height of the fluid level at the reservoirs. Although there may not be...

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... used for MEMS. This alleviates many of the reservations and costs that might inhibit their adoption. Because the MEMS constraint is the minimum gap dimension, the wave bearing in a MEMS machine ... shows the measurements (from a 26:1 scaled-up experimental rig) along with the theoretical predictions based on the assumed geometry. The right-hand frame shows the same meas...

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... τ R is the time of rupture and b is the constant which should be determined from the matching with the far-from-rupture solution. The minimal thickness of the film close to the rupture point is therefore b ξ ᎏ 2 b 2 ᎏ 2 d ᎏ hЈ 0 48 π 2 d 5 σ ᎏ AЈ σ a 2 ᎏ 3d AЈ ᎏ 2 πσ 1 ᎏ d Physics ... of film surface deformations is well-correlated with the wavelength of the most amplified...

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... various examples of their dynamics relevant for MEMS are presented, some of them with reference to the corresponding experimental results. The examples discussed examine isothermal, non-isothermal with ... interfacial jump in the momentum flux, the combination of the fourth and the fifth terms represents the jump in the conductive heat flux at both sides of the interface,...

Ngày tải lên: 10/08/2014, 02:21