Experimental validation of a MACH2 cablegun code

Summary form only given, as follows. A MACH2 based cablegun simulation code has been developed using an optically thin radiation-ablation model. The model relies on two parameters related to the mean specific opacity of the plasma and the optical transmission of the ablating vapor layer. Experiments were performed with cableguns identical to those used for plasma injection into the DECADE plasma opening switch. Two laser interferometer beams placed 2.5 and 5.0 cm downstream of the nozzle exit provided radial scans of the electron number density and a measure of the plasma velocity in the ejected plasma. The time dependent radial profiles of the number density, the plasma velocity, the plasma temperature and the measured mass ablated from the cableguns were used to select values for the unknown model parameters. Comparisons of code predictions with the line-integrated electron number density and with electron number density obtained from Abel inverted interferometer data show good agreement. The code and the data both exhibit the oscillating density and spread in the ejected plasma caused by the oscillating current from the underdamped LRC driving circuit.