Some measurements of the effect of gaseous imperfections on the critical pressure ratio in air and the speed of sound in nitrogen

Coleman dup Donaldson, Jim J. Jones
Aug 1951

Experiments were made to measure the speed of sound in nitrogen at room temperature in the pressure range of 0 to 2000 pounds per square inch, and the critical pressure ratio of air expanded isentropically from stagnation conditions in the same range.

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