FEB氦灰问题研究

本文从现有的氦灰输运和排除的实验数据出发，计算了ＦＥＢ的氦灰积累速率，得到了平衡氦灰浓度，另外，从α粒子平衡方程和等离子体功率平衡方程出发得到的结果与直接从实验数据计算得到的结果相一致。最后，用二维Ｍｏｎｔｅ－Ｃａｒｌｏ程序模拟了排灰效率与偏滤器工程结构参数和靶板附近的等离子体参数之间的敏感性关系。

STUDIES ON FEB HELIUM ASH ISSUES

Utilizing present available experimenal data on alpha removal, time dependent thermal alpha accumulation rates have been calculated assuming that the alpha particles follow classical local prompt thermalization. Allowable effective alpha particle confinement time for FEB normal operation has been assessed from the power balance and alpha particle balance equations. The result is fairly consistent with that calculated directly from the experimental database. Helium poisoning effects are also discussed. Numerical studies on the pumping efficiency of helium removal have been obtained using a 2 D Monte Carlo technique to simulate helium transport in the vicinity of divertor target plate. Some geometrical parameters and divertor plasma parameters sensitive to the pumping efficiency have been studied.