Diode-laser tomography for arcjet plume reconstruction.

Diode-laser absorption tomography is described with which the spatial temperature and the atomic number density distribution of a 3-kW class arcjet can be derived simultaneously by reconstruction of the absorption coefficient field of the arcjet's argon exhaust plume. One can perform various parameter measurements by changing the arcjet's mass-flow rates and discharge currents. The maximum temperature and atomic number density increase with the mass-flow rate and the discharge current. The trend for increase is not always found for a specific input power, although at a fixed mass-flow rate the power increases at that rate.