Eddy Current Flow Meter Measurements in Liquid Sodium at High Temperatures

We present measurement results for the flow rate of liquid sodium at temperatures up to 700°C that were obtained with a high temperature prototype of an immersed Eddy Current Flow Meter. The experimental campaign was conducted at the SOLTEC-2 sodium loop at KIT. The main objective of the experiments is the high temperature qualification of the Eddy Current Flow Meter as part of the safety instrumentation of generation IV liquid metal cooled fast reactors. There it is intended to be used for monitoring the flow rate of the coolant and to detect possible blockages of sub assemblies. Due to the large liquid metal volume, the sensor has to be located close to the sub assemblies, therefore measurements from outside of the vessel are not possible and an immersed sensor is required. We demonstrate the successful application of the immersed Eddy Current Flow Meter at such high temperatures and identify the relevant effects with impact on the sensor performance.