The present work examines line measurements of pressure, temperature, anddensity in high speed, non-isobaric flows emanating from an underexpanded jet nozzle.Line images of rotational and vibrational Raman spectra are collected for a 8-mmlinear laser probe, and are combined onto the same EMCCD detector. Combiningthe two techniques allows for a single-shot measurement of major species, pressure,and temperature in a turbulent non-isobaric environment that is chemically reacting.Temperature measurements along the laser test section are extracted from the rotationalRaman spectrum, whereas major species densities are measured by examiningthe intensities of their respective vibrational Raman lines. Pressure can be calculatedusing an equation of state, in every location along the linear laser probe. The techniquefeasibility is examined by performing measurements of pressure, temperatureand density in a non-reacting underexpanded air jet where the chemical compositionis constant and known. Future work will extend the technique to chemically reactingsupersonic flows with unknown chemical composition.
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