ELECTRON BEAM DENSITY PROBE FOR MEASUREMENTS IN RAREFIED GAS FLOWS

Journal Article · Sun Mar 01 04:00:00 EST 1959 · Journal of Applied Physics (U.S.)

DOI:https://doi.org/10.1063/1.1735151· OSTI ID:4261444

Hurlbut, F C

A instrument is described for the determination of densities in rarefied gas streams which utilizes the attenuation of an electron beam. The electron beam in passage through a rarefied gas becomes scattered in a number of elastic and inelastic processes and decays to a fraction of its initial intensity in the distance of a few electron mean free paths. Where the optical aperture of the detector is suitably small, the familiar linear absorption law applies. The mass absorption coefficient in this case is higher and more favorable for work at the lowest test section densities than in other absorption techniques investigated to the present. The instrurment was used in an investigation of air flows about a sphere and a wedge and in the undisturbed stream. The flow was maintained constant for all portions of the test at Mach 1.95, Re/in. nd 350 deg F oi 200, test section static pressure - 80 mu Hg. Plots of the original and the reduced data show adequate internal consistency and a qualitative conformity with expected configurations. (auth)

• Research Organization: Univ. of California, Berkeley
• Sponsoring Organization: USDOE
• NSA Number: NSA-13-009969
• OSTI ID: 4261444
• Journal Information: Journal of Applied Physics (U.S.), Journal Name: Journal of Applied Physics (U.S.) Vol. Vol: 30; ISSN JAPIA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
CONFIGURATION
ELECTRON BEAMS
GAS FLOW
INSTRUMENTS
RADIATION DETECTORS
SCATTERING