The investigation of fuel retention in fusion experiments is important in view of plasma density control as well as tritium inventory for future fusion reactors. We present a first gas balance of the stellarator Wendelstein 7-X with its inertially cooled graphite divertor. The gas balance is used to estimate the wall inventory and it is found that the wall plays an important and dynamic role, absorbing or releasing particles depending on the plasma conditions. Several different scenarios are presented and the effect of fueling and heating on the wall inventory is assessed. We find that the record duration plasma experiment of 100s required previous shorter plasmas to be successfully conducted.

鉴于等离子体密度控制以及未来聚变反应堆的tri存量，聚变实验中燃料保留的研究非常重要。我们介绍了恒湿器Wendelstein 7-X及其惯性冷却的石墨分流器的首次气体平衡。气体平衡用于估算壁的存量，并且发现壁起着重要的动态作用，根据等离子条件吸收或释放颗粒。提出了几种不同的方案，并评估了加油和加热对墙面存货的影响。我们发现记录持续时间为100s的等离子体实验需要成功地进行先前较短的等离子体。