Based on the variations of the static pressure along the magnetic field line in different divertor operation regimes,the effects of the divertor operation regimes on the plasma parallel flow at the edge of a tokamak are investigated using a one-dimensional fluid model. In low recycling regime,the variation of the static pressure along the field line is obvious from the scrape-off layer（SOL） region near the X-point,and the variation tendency is the same as that of the density.The Mach number of the plasma parallel flow increases along the magnetic field line and the variation is from gentle to sharp.In high recycling regime,the static pressure does not change much except in the near divertor plate region,as a result,the Mach number of the plasma parallel flow varies gently in the SOL region and the most of the divertor region,and it increases rapidly in the near divertor plate region.The variation of the static pressure in weak divertor detachment regime is similar to that in high recycling regime,but the static pressure shows decrease tendency in the SOL region near the X-point,consequently,the Mach number of the plasma parallel flow at X-point is larger than that in high recycling regime.In strong divertor detachment regime,static pressure decreases obviously in the SOL region and away from the divertor plate region,where the static pressure decreases rapidly,and a high Mach plasma parallel flow is observed.Static pressure decreasing while dynamic pressure increasing to keep the total pressure conservation is shown to be a possible cause of the high Mach parallel flow.%我们使用一维流体模型,根据在不同偏滤器运行模式下静压强沿着磁力线方向的分布变化,讨论了偏滤器运行模式对托卡马克边缘区等离子体平行流的影响.低再循环模式下,静压强从X点（X-point）附近的刮削层区域开始明显下降,变化趋势与密度变化趋势一致;等离子体平行流的马赫数在偏滤器区域逐步变大,变化从平缓到迅速.高再循环模式下,静压强在靶板附近的区域迅速下降,在其他区域变化非常小;等离子体平行流的马赫数仅在靠近靶板附近的区域迅速变大,在其他区域变化平缓.在弱脱靶模式下的静压强变化与高再循环模式下类似,不过静压强在X-point附近的刮削层区域开始出现下降的趋势,导致等离子体平行流的马赫数在X-point处的值比在高再循环模式下大.强脱靶模式下,静压强在刮削层区域开始明显下降,在远离靶板的偏滤器区域,静压强迅速下降的地方,观察到高马赫数等离子体平行流.静压强迅速下降引起动压强迅速上升来维持总的压强守恒是在强脱靶状态下产生高马赫数平行流的一种可能驱动机理.
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