In this paper, a method was developed to estimate in-situ the emissivity of the W-coated graphite divertor tiles in the WEST tokamak. This method is based on the double heating method and take advantages of the divertor temperature increase after successive plasma experiments due to the inertial behavior of the plasma facing components. Photonic calculations have been used to disentangle the emitted and the reflected parts in the measured radiances from the infrared system. The uncertainty as well as the robustness of the method have been investigated thanks to the wide IR and thermocouple coverage in the WEST divertor. The results show strong variation of the emissivity along the divertor W surfaces with a factor 4 variation after the experimental campaigns including 18.3 GJ and about 21 000 s of cumulated injected energy and duration, respectively. Finally, the implication of a non-uniform emissivity on heat flux estimation from IR measurements is discussed, showing that non-uniform emissivity must be considered to obtain an accurate heat flux decay width.

在本文中，开发了一种方法来现场估算WEST托卡马克中W涂层的石墨偏滤器瓦的发射率。该方法基于双重加热方法，并利用了连续等离子体实验后由于面对等离子体的组件的惯性行为而使偏滤器温度升高的优势。光子计算已用于解散红外系统中测得的辐射中的发射部分和反射部分。由于WEST偏滤器的红外和热电偶覆盖范围广，已经研究了该方法的不确定性和鲁棒性。结果表明，在进行了包括18.3 GJ和大约21 000 s的累计注入能量和持续时间的实验运动之后，沿偏滤器W表面的发射率发生了4倍的强烈变化，分别。最后，讨论了不均匀发射率对红外测量热通量估计的影响，表明必须考虑不均匀发射率才能获得准确的热通量衰减宽度。