| Popis: |
A low-density gasdynamic facility, suitable for measurement of mass flow through small (approximately 1 mm diameter) nozzles, tubes, and orifices, was designed and constructed. The system is capable of producing and measuring mass flows at 100:1 upstream/downstream pressure ratios for the entire spectrum from continuum to free molecular flow. Results of preliminary tests on an orifice are shown and compared with the work of previous investigators. The regime of transition flow is apparently shown to extend to higher Knudsen numbers than previously postulated. The ratio, of actual mass flow to theoretical free-molecule mass flow is shown to increase smoothly from a limiting value of 1.0 at high Knudsen numbers to an apparent limiting value at very low continuum-flow Knudsen numbers. |
