QUEST (Q-shu university experiment with steady state spherical tokamak) is a midsize spherical tokamak capable of steady-state operation, comprising all-metal plasma-facing walls and a hot wall (HW) to address issues pertaining to fuel particle balance. The HW was installed summer 2014. Quantitative analysis pertaining to the HW at 373K is carried out, and clarify the quantitative impact of shot history that obviously appears in wall stored hydrogen just before the discharge at the wall temperature. The model indicates the plasma-induced deposition layer play an essential role in fuel particle balance. A clear temperature dependence of fuel recycling was observed using outgassing just after plasma termination and played an essential role in regulation of particle balance. Consequently, long duration discharges lasting more than 1h has been obtained at wall temperature, T_W < 423K in the range of 40-60kW of RF power and, similarly, a 6 h discharge could be achieved at T_W=473K using 20 kW of injected RF power.

QUEST（Q-shu大学的稳态球形托卡马克实验）是一种能够稳态运行的中型球形托卡马克，由全金属等离子壁和热壁（HW）组成，以解决与燃料颗粒平衡有关的问题。硬件安装于2014年夏季。对373K硬件进行了定量分析，并阐明了在壁温放电之前壁储氢中明显出现的弹丸历史对定量的影响。该模型表明，等离子体诱导的沉积层在燃料颗粒平衡中起着至关重要的作用。在等离子终止后立即使用脱气观察到燃料再循环的明显温度依赖性，并且在调节颗粒平衡方面起着至关重要的作用。最后，_W <423K在40至60kW的RF功率范围内，同样，使用20 kW注入的RF功率，在T _W = 473K时可实现6 h放电。