运动流体界面Rayleigh-Taylor不稳定性研究
摘要
Starting from the nonrelativistic fluid and relativistic fluid models, we study the linear growth of the Rayleigh-Taylor instability (RTI) at the interface of two ideal fluids moving with certain speed under a gravitational field, where the fluid velocity is along the gravitational field and is perpendicular to interface. Calculation shows that, the RTI growth rate for nonrelativistic fluids is independent of its reference frame or the fluid velocity. A general formula of the RTI growth rate is obtained for relativistic fluids. It shows that both the relativistic thermal pressure and macroscopic fluid velocity tend to suppress the RTI growth. Physically, when the thermal velocities of microparticles of the relativistic fluids are considerable as compared to the light speed in vacuum, the contribution of the thermal pressure to the fluid inertia cannot be ignored. Also when the fluid velocities are not negligible as compared to the light speed, the effect of relativistic-mass-increase leads to the decreased RTI growth rate. The latter is basically consistent with the time transformation effect in different reference frames.