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Title: Molecular dynamics simulations of microscale fluid transport

Recent advances in micro-science and technology, like Micro-Electro-Mechanical Systems (MEMS), have generated a group of unique liquid flow problems that involve characteristic length scales of a Micron. Also, in manufacturing processes such as coatings, current continuum models are unable to predict microscale physical phenomena that appear in these non-equilibrium systems. It is suspected that in these systems, molecular-level processes can control the interfacial energy and viscoelastic properties at the liquid/solid boundary. A massively parallel molecular dynamics (MD) code has been developed to better understand microscale transport mechanisms, fluid-structure interactions, and scale effects in micro-domains. Specifically, this MD code has been used to analyze liquid channel flow problems for a variety of channel widths, e.g. 0.005-0.05 microns. This report presents results from MD simulations of Poiseuille flow and Couette flow problems and addresses both scaling and modeling issues. For Poiseuille flow, the numerical predictions are compared with existing data to investigate the variation of the friction factor with channel width. For Couette flow, the numerical predictions are used to determine the degree of slip at the liquid/solid boundary. Finally, the results also indicate that shear direction with respect to the wall lattice orientation can be very important. Simulation results of microscalemore » Couette flow and microscale Poiseuille flow for two different surface structures and two different shear directions will be presented.« less
Authors:
; ; ;
Publication Date:
OSTI Identifier:
574190
Report Number(s):
SAND--98-0336
ON: DE98003215; TRN: 98:001224
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Feb 1998
Research Org:
Sandia National Labs., Albuquerque, NM (United States)
Sponsoring Org:
USDOE Assistant Secretary for Human Resources and Administration, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; MICROSTRUCTURE; COUETTE FLOW; LAMINAR FLOW; MOLECULAR DYNAMICS METHOD; COMPUTERIZED SIMULATION; PARALLEL PROCESSING; HYDRAULIC TRANSPORT; SCALING LAWS