Laser-sustained plasmas in forced argon convective flow. I - Experimental studies

The results of an experimental investigation of the properties of laser-sustained plasmas in argon at forced convective flow speeds of 0.4-4.5 m/s are reported in this paper. At these speeds, the incident flow rate has a significant effect on the shape, size, and position of the plasma, which in turn affect the power absorption, thermal radiation, and total energy conversion efficiency of the plasma. In addition to the incident flow rate, the focusing geometry, chamber pressure, and laser power were varied as parameters in the experiments. The thermal conversion efficiency was found to range 9-38%, depending on the various parameters.