Thermal Analysis on Various Design Concepts of ITER Divertor Langmuir Probes

The thermal performance of the divertor Langmuir probe conceptual design developed for the ITER divertor, which consists of a shielded probe bolted to a copper heat sink, has been predicted by the finite element analysis package ANSYS to have a high risk of damage due to poor heat transfer ability. In order to mitigate this risk, three alternative designs focusing on improving heat conduction have been proposed, and the power-handling abilities, damage risk, and interface challenges of the three designs have been compared. First simulation results indicate that a design involving casting a tungsten probe sensor into a copper heat sink could provide adequate heat-handling capacity. Elasto-plastic stress analysis will be needed to evaluate the thermal stresses at W/Cu interface in our future work. Langmuir probe prototypes will be prepared and high heat flux tests will be performed on electron beam facilities at the Southwestern Institute of Physics to verify the probe functionality once analysis has identified a suitable candidate design.