Sampling Probe for Instantaneous Mass Spectrometric Analysis of Rarefied Enthalpy Flow

摘要

An aerodynamically shaped probe was developed for instantaneous mass spectrometric analyses of gas samples taken from low density, high enthalpy, hypersonic flows. The requisite .00001 torr operating pressure for a quadrupole mass spectrometer mounted in the water-cooled probe was established and maintained by a liquid-hydrogen cryopump. During an initial series of 5-min tests, the detected composition of an arc-heated airflow with a stagnation condition of approximately 10 atm at 3000K agreed well with a nonequilibrium flow expansion calculation. (Author)