In the Experimental Advanced Superconducting Tokamak (EAST), the water in the cooling channels of the upper divertor is difficult to be pushed out by the current drainage system resulting in the possible divertor damage. Therefore, studies on the draining process using the gas pushing for this divertor is essential to improve the current drainage system. In this paper, the hydraulic characteristics of the developing gas-liquid two-phase flow were investigated in detail by using the FLUENT code. The results showed that the pressure difference between the inlet and outlet of the cooling channel should be larger than 4 kPa to effectively blow out the residual water from the cooling channels by the nitrogen gas pressure. Also, it was found that the draining process can be divided into five stages in regards to the different hydraulic characteristics, such as the flow velocity, the draining water flow rate, and the pressure distribution. These results will provide a theoretical basis for future improvements in the EAST drainage systems.

在实验高级超导托卡马克（EAST）中，当前排水系统难以将上部分流器冷却通道中的水推出，从而可能导致分流器损坏。因此，对于使用该分流器的气体推动进行排水过程的研究对于改善当前的排水系统至关重要。本文使用FLUENT代码详细研究了正在开发的气液两相流的水力特性。结果表明，冷却通道入口和出口之间的压力差应大于4 kPa，以通过氮气压力有效地吹出冷却通道中的残留水。此外，还发现，根据不同的水力特性，排水过程可以分为五个阶段，例如流速，排水流量和压力分布。这些结果将为EAST排水系统的未来改进提供理论依据。