EFDA-JET-CP(12)02/37
Calorimetry of the JET ITER-Like Wall Components
As part of the ILW project, new diagnostics have been installed in order to protect the Plasma-Facing Components (PFC). Here we present the diagnostics used to monitor the PFC temperature, thermocouples and cameras, and assess the consistency of their measurements. In dedicated limited L-mode plasmas, the surface of the limiter tiles are heated up to 900°C. The comparison of surface temperature measurements from IR and near IR cameras, which have been calibrated against a black-body source, leads to a Be emissivity of 0.18, comparable with the theoretical one. Energy calculation derived from thermocouples data, which are embedded in both limiters and divertor target plates (W-coated CFC), is compared to a 1D model based on thermal quadrupole approach (benchmarked with an ANSYS model) associated to an inversion computation. The analysis shows a good energy balance can be achieved within the errorbar of the model, assessed to be of 30 percent.