Accession Number : ADA303678

Title :   Study of Fluid Dynamics with Integrated Micro Sensors.

Descriptive Note : Final technical rept. 30 Jun 93-30 Jun 95,

Corporate Author : CALIFORNIA UNIV LOS ANGELES DEPT OF MECHANICAL AEROSPACE AND NUCLEAR ENGINEER ING

Personal Author(s) : Ho, Chih-Ming

PDF Url : ADA303678

Report Date : 17 NOV 1995

Pagination or Media Count : 15

Abstract : The drastic size reduction in the micromachine field results in the breakdown of the scaling laws used in traditional engineering fields because the large length scale change is significant enough such that the equations governing the momentum and energy balances need to be re-examined. For example, the gas flow in a micromachine might not be considered as continuum anymore. In addition, the inter-link among these fields becomes important in micron scales such that the surface physics and chemistry may significantly affect the boundary conditions in fluid mechanics. In this study, a very simple flow configuration, flow through a straight channel, was used to investigate the challenges in the micro world. While monatomic gas, helium, was used as the working medium, the mass flow rate and streamwise pressure distribution can be calculated from the Navier-Stokes equation with a slip flow boundary condition. However, the measured pressure distributions of polyatomic gases, e.g. oxygen, nitrogen and carbon dioxide, do not agree with the analytical results. It is surprising that these polyatomic gases have much lower Knudsen number than that of helium. (AN)

Descriptors :   *MASS FLOW, *MICROELECTRONICS, *PRESSURE DISTRIBUTION, *GAS FLOW, PRESSURE GRADIENTS, MICROSTRUCTURE, POLYATOMIC MOLECULES, CHIPS(ELECTRONICS), INTEGRATED CIRCUITS, COMPUTATIONAL FLUID DYNAMICS, PRESSURE MEASUREMENT, GAS DYNAMICS, NITROGEN, OXYGEN, ELECTROMECHANICAL DEVICES, DIATOMIC MOLECULES, HELIUM, CARBON DIOXIDE, NAVIER STOKES EQUATIONS, CHANNEL FLOW, SLIP FLOW, MOMENTUM TRANSFER, KNUDSEN NUMBER, MICROCHANNEL PLATES.

Subject Categories : Electrical and Electronic Equipment
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE