Laser-induced-fluorescence characteristics of a helium arcjet flow
- Cite this article as:
- Walker, Q. & Cappelli, M. Appl Phys B (2002) 75: 717. doi:10.1007/s00340-002-1050-1
Laser-induced fluorescence is used to characterize the axial velocity and temperature field at the exit plane of a low-power helium arcjet. Two cases were examined, one in which the mass-flow rate was changed at a constant current, and the other where the current was changed at a constant mass-flow rate. At constant mass-flow rate, the velocity scales with the increase in power. At constant current, a higher specific energy results in an unexpected lower mean exit velocity. The temperature profiles show that the nozzle-wall temperature is greater than the mean exit temperature. Along the axis of the arcjet, these measurements indicate the presence of a shock less than one nozzle diameter downstream of the exit.