Experimental Development and Demonstration of Ultrasonic Measurement Diagnostics for Sodium Fast Reactor Thermal-hydraulics

Abstract

Project SummaryThis research project will address some of the principal technology issues related to sodium-cooled fast reactors (SFR), primarily the development and demonstration of ultrasonic measurement diagnostics linked to effective thermal convective sensing under normal and off-normal conditions. Sodium is wellsuited as a heat transfer medium for the SFR. However, because it is chemically reactive and optically opaque, it presents engineering accessibility constraints relative to operations and maintenance (O&M) and in-service inspection (lSI) technologies that are currently used for light water reactors. Thus, there are limited sensing options for conducting thermohydraulic measurements under normal conditions and off-normal events (maintenance, unanticipated events). Acoustic methods, primarily ultrasonics, are a key measurement technology with applications in non-destructive testing, component imaging, thermometry, and velocimetry. This project would have yielded a better quantitative and qualitative understanding of the thermohydraulic condition of sodium under varied flow conditions. The scope of work will evaluate and demonstrate ultrasonic technologies and define instrumentation options for the SFR. Under the workscope, the researchers accomplished and/or report the following:• A sodium loop, just under 10 liters, was designed, constructed, and operated but only tested in water.One of the two test sections was a natural convection heat transfer experiment wherein ultrasonic velocimetry was tested. The loop received design and safety review approval from the Center for Advanced Energy Studies (CAES) and is thus ready to be operated with sodium, given CAES' preparedness to receive sodium. • Development and demonstration of ultrasonic thermometry was not fulfilled. However, we learned that this can essentially be done by signal processing with the well-known variation of the acoustic velocity in sodium. Therefore the dual-purpose velocimetry and thermometry is still possible.• Testing of a compact sodium-to-supercritical C0 2 heat exchanger was not realized. However a prototype compact heat exchanger manufactured by Tranter was procured. It will be tested and thus leverage in an ongoing NEUP project.• Limited natural convective transient heat transfer and velocimetry data was obtained using the MetFlow Dual ultrasonic Doppler velocimetry profiler (UVP). A number of transducers rated up to 150°C are being leverage in another ongoing sodium project.• Access to the ANL sodium plugging experiment was not provided as indicated by a letter from ANL in 2007.• The project experienced a number of transfers, delays and departure of co-Pis, from Kansas State University to University ofldaho. A final ill-informed 'work stoppage' order at CAES made completing the SOW all but impossible. Unexpended funds were returned to DOE-ID.• There has been interest expressed by a FFRDC to assume possession of the project related hardware. BackgroundThe international sodium fast reactor R&D eff01t, most recently summarized in ...