Measurement of Argon-Density Nonuniformities in Argon-Cesium MHD Plasmas

The heavy particle-density nonuniformities correlated with the observed arc structure of closed-cycle magnetohydrodynamic (MHD) generators are measured with a quantitative schlieren technique called the laser-beam deflection method. The experiments are performed with a shock-tube MHD generator working with an atmospheric cesium-seeded argon plasma. The evaluation of argon density and temperature profiles from the experiments is discussed and the results are presented. It is shown that an argon-density nonuniformity is associated with every arc, and that the argon density within the arc is about 25 percent lower than the density outside.