... 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 simulation methods are more fundamental, they
require ... “Numerical Modeling of Micromechanical Devices Using the Direct
Simulation Monte Carlo Method,” J. Fluids Eng. 118 , pp. 464–69.
6-2 6 MEMS: Introduction and Fundamental...
... 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 ... Reduced-Order Models for Complex Geometries
11. 6 Lubrication in Rotating Devices 1 1-9
11. 7 Constraints on MEMS Bearing Geometries 1 1-1 1
Device Aspect Ratio • Min...
... 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...
... 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. 117 , pp. 3–5.
Gad- el- Hak, M. (1999) The Fluid Mechanics of Microdevices: The Freeman Scholar Lecture,” J. Fluids
Eng. 121, pp. 5–33.
G...
... 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 ... and
σ
T
are the tangential momentum and thermal accommodation coef-
ficients respectively. The accommodation coefficients model the momentum and energy exchange of gas mol-...
... and Ducts at Micro and Nano
Scales,” Microscale Thermophys. Eng. 3, p. 43.
Beskok, A. (2002) “Molecular-Based Microfluidic Simulation Models,” in Handbook of MEMS, 1st ed.,
M. Gad- el- Hak, ed., CRC ... 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-
i...
... 1997]. The 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 ... region 0 Յ x Յ 1 m. The first-order
8-2 8 MEMS: Introduction and Fundamentals
y/y
max
0.0
0.5
1.0
0.0 1.0 2.0 3.0 4.0 5.0
x/y
max
FIGURE 8.29
Microchannel geometry...
... 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...
... 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,...