Accession Number:

ADA422298

Title:

Scaled-Up Nonequilibrium Air Plasmas

Descriptive Note:

Final technical rept. 1 Jun 2001-31 Jan 2004

Corporate Author:

STANFORD UNIV CA DEPT OF MECHANICAL ENGINEERING

Report Date:

2004-01-01

Pagination or Media Count:

88.0

Abstract:

Experimental investigations of flowplasma interactions in a DC discharge placed in a transverse preheated air flow confirm the role of the gas heating effect. The volume of plasma produced by the discharge is found to decrease when the air flow increases. This counterintuitive result is analyzed through measurements of the reduced field strength EN profile in the discharge. When the flow velocity increases, the gas traversing the discharge region has less time to undergo vibrational-translational energy transfer and therefore it does not heat up as much. Lower temperature results in higher gas density N, thereby decreasing the EN further downstream the flow. Since the rate coefficients of electron-impact processes are controlled by the EN, the discharge volume tends to be larger in the slower flows.

Subject Categories:

  • Fluid Mechanics
  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE