低温冷冻靶是惯性约束核聚变装置的关键部件之一。冷冻靶靶丸位于黑腔内部, 需要利用微管完成燃料充注。针对燃料在微管内发生气液相变后流入靶丸这一关键过程, 研究了微通道流体与常规流体流动传热的差异。基于微通道特性对流体流动传热方程进行修正, 同时建立了气液相变模型, 对微充气管内燃料充注过程进行了数值计算分析。得到重力和表面张力的影响, 在微通道中, 重力作用可以忽略, 表面张力起重要作用。得到了微尺度效应包括速度滑移和温度跳跃对流动传热过程的影响。对多种充气管结构进行比较分析, 为选型提供指导。通过选择不同进口条件和出口条件, 对充注量控制和充注条件选择提供了指导方案, 实际充注时需要同时提高进口温度和压力, 保证连续可控充注。

Cryogenic target is one of the critical component in inertial confinement fusion, which is assembled inside a hohlraum needed to be filled by fill tubes. In this paper, a microchannel model is established based on the analysis of the big difference between the microchannel and the conventional channel on flow and heat transfer characteristics. The modeling is implemented with FLUENT software and the correction of Navier-Stokes equations is inserted through UDF. From the results of simulation, the effect of gravity can be neglected while that of surface tension should be taken into consideration. Velocity slip and temperature jump are also calculated for their significant influence on flow and heat transfer in the microchannel. Three different fill tube models are compared to provide a suitable type for experiment design. Choosing different boundary conditions, certain filling of fuel could be confirmed. During the filling process, the temperature and pressure of inlet should be increased gradually with the increasing temperature and pressure of outlet to guarantee continuous controlled filling.