Instrumentation for Temperature and Heat Flux Measurement on a Solid Surface under BWR Operating Conditions
2015 (English)In: Proceedings of the 16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-16), American Nuclear Society , 2015, 5962-5975 p.Conference paper (Refereed)
A new experimental facility has been developed at KTH Royal Institute of Technology to measure temperature and heat flux propagations in solid walls due to mixing of non-isothermal water streams in their vicinity. The main purpose of the measurements has been to obtain a high-precision experimental database suitable for validation of Computational Fluid Dynamics (CFD) codes. Consequently, a set of experiments have been performed in a test section simulating the annular region in the BWR control-rod guide tubes. Since preliminary CFD results implied that 0.1-1 Hz temperature oscillations were to be expected, this experimental research intends to assess the magnitude of temperature fluctuations within the abovementioned frequency range. To this end, water and wall temperatures have been measured in the innermost part of the test-section annulus, with a variety of boundary conditions. As thermocouples would otherwise be available at few axial and azimuthal coordinates only, the tube they are installed on has been lifted, lowered and rotated by a software-controlled motor to record temperature fluctuations in the whole mixing region. At each measurement point, data have been collected over a time long enough to detect the existence of the aforesaid fluctuations. Moreover, an uncertainty analysis has been carried out concerning water temperatures. Thermocouples meant to monitor these temperatures have been modelled with a finite-element method for this very purpose. The wall heat flux has also been estimated using experimental data, thanks to a corrected finite-difference Crank-Nicolson scheme.
Place, publisher, year, edition, pages
American Nuclear Society , 2015. 5962-5975 p.
Wall temperature measurement, heat flux measurement, measurement uncertainty, temperature fluctuations, thermal fatigue
IdentifiersURN: urn:nbn:se:kth:diva-186290ScopusID: 2-s2.0-84964053806ISBN: 978-151081184-3OAI: oai:DiVA.org:kth-186290DiVA: diva2:926776
16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-16), Chicago,2015
FunderSwedish Radiation Safety Authority, 47385
QC 201605112016-05-092016-05-092016-05-24Bibliographically approved