EXPERIMENTAL DETERMINATION OF THE VISCOSITY OF AIR IN THE GASEOUS STATE AT LOW TEMPERATURES AND PRESSURES
Rept. for 12 June 61-11 Dec 1962
BATTELLE MEMORIAL INST COLUMBUS OH
Pagination or Media Count:
A program was undertaken to determine the viscos ity of gaseous air at cryogenic temperatures for use in the interpretation of hypervelocity wind tunnel data. Data were obtained over a tempera ture range of 92.7 to 198.0 R using an oscillat ing-disk viscosimeter designed for cryogenic operation. Data were also obtained at greatly reduced pressures where the slip effect becomes important. This was done to aid in the evalua tion of the lowest temperature data, where re duced pressures were mandatory in order to avoid condensation. A fit of the viscosity data to a temperature-viscosity equation of the Sutherland form was made. The data obtained at the lowest temperatures deviated from the behavior predicted by the Sutherland Formula. A minor deviation occurred in the vicinity of 140 R, while the major deviation occurred at the lowest tempera ture of 92.7 R. At this latter temperature, the measured air drag was essentially zero. No sub stantiated explanation has been given for this latter behavior.