Velocity measuring techniques in liquid lithium systems for fusion devises

The efficiency of applying liquid-metal lithium systems as plasma-facing components (PFC) in fusion devices is determined by the effectiveness of heat removal and the extraction of cold fuel (hydrogen isotopes) from the reactor chamber. Both of these parameters directly depend on the average flow rate of the metal in both the divertor region and the pipes of the system. Additionally, it is important to analyze the possibility and the most probable areas of accumulation of solid-phase lithium hydrides. These solid impurities can lead not only to clogging of flow in the system but also to increased tritium accumulation increasing the radiological safety issues. Therefore, it is extremely important to be able to measure the flow rate of liquid lithium in any part of the liquid-metal system, this includes not only the average volumetric flow rate but also the velocity distribution across the cross-section of the flow. This work is devoted to examining the use of various measurement systems to determine the liquid lithium flow rate on the divertor plate and within pipes of the system. After an initial literature review a suitable method will be selected and experiments to test and calibration diagnostics will be performed. This abstract will present on the initial review and first results from this process.