LOW DENSITY HIGH TEMPERATURE GAS DYNAMICS.
Abstract
Surface pressures on a flat plate with sharp leading edge were measured in a M = 1.5 monatomic gas flow. The results were in essential agreement with those recorded for a diatomic gas, but differed quantitatively from a recent theory based on a discrete ordinate solution of the BGK equation. The modulated hot-wire probe was proven conclusively to provide a measurement of local mass flux in a hypersonic flow. Surveys performed in a low density free jet showed very clearly the initial disturbance produced by the thick surrounding shock structure. The upstream influence of a sharp flat plate was measured with the modulated hot wire probe. The disturbance field was symmetrical about the leading edge and extended upstream for approximately three mean-free-paths based on a body-free stream collision. Thermographic phosphors were determined to exhibit a sensitivity of 8% change in output light intensity per deg C and to have an equivalent noise figure of 0.1C; thus they will be suitable for measuring local surface temperature at sharp leading edges. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 30, 1969
- Accession Number
- AD0706906
Entities
People
- J. F. Wendt
- Jean J. Smolderen
Organizations
- von Kármán Institute for Fluid Dynamics