TRANSLATIONAL FREEZING IN FREELY EXPANDING JETS.
Abstract
An aerodynamic molecular beam system has been used for the examination of some of the nonequilibrium aspects of the fluid mechanics of a freely expanding jet formed by operating a converging nozzle at large pressure ratio. The characteristics of the jet have been observed by measuring the distribution of speeds in beams of argon formed by skimming off all but the core of the nozzle flow. The source Knudsen number dependence of translational freezing agrees reasonably well with previously reported results at small values of source Knudsen number. At larger values of source Knudsen number, however, the source Knudsen number dependence of translational freezing is substantially different from that based on an equilibrium expansion process; and the observed differential intensity distributions differ appreciably from those corresponding to equilibrium states throughout the expansion. Experimental results presented include the complete range of accessible source Knudsen numbers and are shown to be independent of apparatus limitations. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1966
- Accession Number
- AD0487167
Entities
People
- John A. Phipps
- John E. Scott Jr.
Organizations
- University of Virginia