The linear mercury diffusion pump is proposed as the primary pump for sustaining the continuous working of KALPUREX (Karlsruhe liquid metal based pumping process for fusion reactor exhaust gases), which is considered as the exhaust pumping solution for reducing the tritium inventory in future fusion reactor with the fuel cycle based on the Direct Internal Recycling (DIR) concept. In this work, a preliminary simulation study of the linear mercury diffusion pump (LDP) is performed based on the Direct Simulation Monte Carlo (DSMC) method. While the dsmcFoam solver in the OpenFOAM platform is used, the inlet model named by fixed mass-flow-rate (FixedMFR) model is developed to control the mass flow rate into the pump, in accord with the condition of the experiment in 1950s. The simulated pumping speeds are in reasonable agreement with the experimental results when the pressure is in the range of 1 × 10⁻² ~ 2 × 10⁻² Pa, which implies that the DSMC model can be used for simulating the performance of the LDP. It should be noted that in the preliminary DSMC model, the mesh size is too large. Due to the large mesh size, the expansion of the mercury vapor steam is overestimated and the pumping speed is underestimated. Further work is required to find a proper way to generate the computational mesh for predicting the pumping performance of the LDP accurately and effectively.

线性汞扩散泵被提议作为维持 KALPUREX（卡尔斯鲁厄液态金属基聚变反应堆废气抽吸工艺）连续工作的主泵，被认为是减少未来聚变反应堆中氚存量的抽吸解决方案基于直接内部循环 (DIR) 概念的燃料循环。在这项工作中，基于直接模拟蒙特卡罗 (DSMC) 方法对线性汞扩散泵 (LDP) 进行了初步模拟研究。在使用OpenFOAM平台中的dsmcFoam求解器的同时，根据1950年代的实验情况，开发了以固定质量流量（FixedMFR）模型命名的入口模型来控制进入泵的质量流量。^-2 ~ 2 × 10 ^-2 Pa，这意味着 DSMC 模型可用于模拟 LDP 的性能。需要注意的是，在初步的 DSMC 模型中，网格尺寸过大。由于目数较大，汞蒸气蒸汽的膨胀被高估，抽速被低估。需要进一步的工作来找到一种正确的方法来生成计算网格，以准确有效地预测 LDP 的泵送性能。