Effect of EAST liquid lithium limiter distributor box on flow of lithium

doi:10.16568/j.0254-6086.201704010

Abstract

Abstract:

Numerical simulation method is applied on different sizes, shapes, and surface conductivity of distributor channels to observe the effects of the structure and the surface conductivity of distributor channels on the flow of liquid lithium. The calculated results show that the smaller width of distributor channels is, the more uniform the outlet speed of liquid lithium is, and the smaller the peak velocity is. On the contrary, the smaller width of distributor channels is, the higher the pressure loss is between the inlet and outlet. Furthermore, the better the surface conductivity is, the higher the MHD pressure drop is as well. In comparison with the rectangular distributor channels, the outlet velocity distribution of circular and elliptic distributor channels is much more uniform. In addition, the thermal balance calculation of limiter can ensure the safe and stable operation of the flow liquid lithium limiter. The above calculated results have important guiding significance for the parameter designing of distributor, the selection of electromagnetic pump, and the design of the cooling system.

Key words: EAST tokamak, Liquid lithium limiter, Distributor, MHD effects

摘要：

为考察溢流孔结构几何参数及壁面电导率对液态锂流动的影响，通过数值模拟方法对不同尺寸、形状及壁面电导率的溢流孔中液态锂的流动进行了数值模拟。结果表明：溢流孔的截面宽度越小，其出口的速度分布越均匀，速度峰值也越小，但溢流孔进出口之间的压力降会显著增加；且随着壁面电导率增大，MHD压降也随之增大。对于圆形及椭圆形截面的溢流孔，其出口的速度分布远比矩形溢流孔均匀。另外，关于限制器热平衡的计算有助于保证限制器的安全稳定运行。结果对分配盒几何参数的设计、电磁泵及冷却系统的设计具有重要的指导意义。

关键词: EAST装置, 液态锂限制器, 分配盒, MHD效应

CLC Number:

TL62+4

HU Le-Xin, YANG Qin-Xi, SONG Wei, SONG Yun-Tao, ZUO Gui-Zhong, HU Jian-Shen. Effect of EAST liquid lithium limiter distributor box on flow of lithium[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2017, 37(4): 429-435.

胡乐星，杨庆喜，宋伟，宋云涛，左桂忠，胡建生. EAST液态锂限制器分配盒参数对锂流动性影响[J]. 核聚变与等离子体物理, 2017, 37(4): 429-435.

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