Numerical simulation of the effect of plasma ion viscosity on the heating and compression in dynamic Z-pinch implosions

This paper uses a one-dimensional two-temperature magnetohydrodynamic model to simulate the Z-pinch process in deuterium plasma. The onset time of viscous effects is determined using the Reynolds number. The energy evolution and temperature profile during the implosion process, with and without viscosity, are systematically compared. Results reveal that viscosity significantly influences system implosion performance during the later stages of Z-pinch, particularly after 38.4 ns in the reflected-shock and expansion stages. Specifically, viscosity reduces the implosion speed and shock propagation velocity. It smooths the density distribution and delays the maximum compression time by approximately 3.3 ns. Additionally, viscosity enhances the conversion of kinetic energy to thermal energy, raising the peak temperature of electrons while lowering temperature of ions.