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Search Publications by: Keith A Gillis (Fed)

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Displaying 76 - 91 of 91

An Improved Greenspan Acoustic Viscometer

September 1, 2000
Author(s)
J Wilhelm, Keith A. Gillis, J B. Mehl, Michael R. Moldover
We improved the Greenspan acoustic viscometer (double Helmholtz resonator) to measure the viscosity of gases at temperatures from 250 K to 400 K and at pressures up to 3.4 MPa. In anticipation of handling corrosive gases, all wetted parts of the apparatus

Primary Acoustic Thermometer for Use Up to 800 K

April 1, 1999
Author(s)
Dean C. Ripple, Dana R. Defibaugh, Keith A. Gillis, Michael R. Moldover
Primary acoustic thermometers determine the thermodynamic temperature of a monatomic gas from measurements of the speed of sound in the gas. Here, we describe the design and construction of an acoustic thermometer designed to operate at temperatures up to

Acoustic Methods for Transport Properties Measurements in Gases

June 1, 1998
Author(s)
Keith A. Gillis, J B. Mehl, Michael R. Moldover
Two novel acoustic resonators have been developed, one for measuring the viscosity and a second for measuring the Prandtl number of gases. For viscosity measurements, we use a double Helmholtz resonator called the Greenspan viscometer. The Greenspan