Diagnostics of an argon arcjet plume with a diode laser

Abstract

The diode-laser absorption technique was applied for simultaneous velocity and temperature measurements of an argon plume exhausted by an arcjet. The Ar I absorption line at 811.531 nm was taken as the center absorption line. The velocity and the temperature were derived from the Doppler shift in the absorption profiles and the full width at half-maximum of the plume absorption profile, respectively. From the measured plume velocity and temperature, the total enthalpy of the exhausted plume, the thrust efficiency, and the thermal efficiency of the arcjet were derived, and the performance of the arcjet was examined. The results are demonstrated to agree with results derived by other methods, and the technique can be applied to the measurement of other arcjet systems without much modification.

Application of simulated annealing for multispectral tomography

“…For simple symmetric distributions of temperature and concentration, algorithms based on the Abel inversion provided satisfactory performance [2,3,16]. For more complicated distributions, a method involving the use of Karhunen-Loeve basis functions has been developed and demonstrated to provide accurate reconstructions with as few as twenty projection locations [6].…”

Arc-heater as an Atomic Oxygen Generator

“…Here, a brief description of the theory of laser absorption spectroscopy is summarized. More details are shown in reference [11,12].…”

Quantitative Spectral Radiance Measurements in the HYMETS Arc Jet

“…Diode laser absorption has been demonstrated for making simultaneous velocity and temperature measurements of an argon arcjet plume. 3 Oxygen (O)-atom and nitrogen (N)-atom laser-induced fluorescence (LIF) have been used to provide temperature, velocity and species concentration (number density) measurements at a single point or along a line. 4,5,6 NO LIF and O-atom LIF have previously been used in arcjets to measure translational temperatures of O and rotational temperatures of NO.…”