MITIGATION OF THE RAYLEIGH-TAYLOR INSTABILITY BY SHEARED AXIAL FLOWS

The stabilizing effect of sheared axial flows on the Rayleigh-Taylor i nstability in Z-pinch implosions is investigated. Dispersion relations are derived that include the effects of a density discontinuity and a sheared how which produce the Rayleigh-Taylor and Kelvin-Helmholtz in stabilities. The dispersion relations are examined in two limiting cas es of practical interest, a uniform plasma implosion and an annular pl asma implosion. The analytical results show a region of parameter spac e which provides complete stability. The analytical model is verified with nonlinear calculations using experimental implosion parameters an d geometries. The results indicate that mitigation of the Rayleigh-Tay lor instability is possible with a sufficient sheared axial flow. [S10 70-664X(98)03406-5]