New Version of the KTM Lithium Divertor

At present, the Kazakhstan Tokamak for Material testing (KTM) project is in progress. The optimization of innovative design elements of the divertor is carried out at the KTM, in addition to studying materials applied for fusion technologies. The design of the lithium divertor module based on lithium capillary porous systems has been developed and tested successfully in real tokamak conditions. In this design, the problem of removing high-density heat flows is solved by using liquid metal coolant based on the Na–K eutectic alloy. The requirements for the improved safety and the divertor design compatibility with other in-vessel water-cooled elements of the tokamak and temperature limitation of the receiving lithium surface to the level <600°C at the heat flows of 10–20 MW/m2 stipulated a new design solution of the divertor experimental module and the use of a totally new coolant—water flow dispersed with gas (gas-water spray). In the paper, the design solutions of the new version of the module, the coolant parameters, and the cooling system layout are described and substantiated. The experimental results on determining the heat transfer coefficient of the coolant based on gas-water spray are considered.