考虑轻杂质时离心级联中组分分布的数值模拟

Numerical simulation of light impurity production and diffusion in a centrifugal cascade

为了清楚地了解离心机级联中轻杂质的传播与分布,对利用离心法获取同位素过程中存在的轻杂质问题进行了数值模拟。根据实际的物理过程,建立了新的质量损失模型及轻杂质(HF)产生模型。数值模拟中将反映物质守恒的微分方程进行差分处理,以W F6为工作介质,考虑腐蚀损耗、供料中的轻杂质及离心机级联系统漏率,求解差分方程组,得到了离心级联中各组分的丰度分布,并与旧的模型进行了比较。数值计算结果显示新模型得到的轻杂质丰度在精料端的积累量远高于旧模型,理论上该模型能够更准确地反映离心级联中轻杂质传播与分布情况。

The diffusion of light impurities during isotope separation in a centrifugal cascade was analyzed numerically using a model which describes material losses and the production of a light impurity （HF）. Numerical solution of the mass conservation equation using WF6 as the process gas considered the light impurity both in the feed and from chemical reactions of the process gas with leakage air and structural materials in the cascade. Comparison of the production of light impurities with productions of other methods shows that the model predicts a much higher concentration of the light impurity at the production end than previous models because the model more accurately reflects the diffusion of the light impurity.