CFD Investigation of Supercritical Water Flow and Heat Transfer in a Rod Bundle with Grid Spacers
2015 (English)In: Proceedings of the 7th International Symposium on Supercritical Water-Cooled Reactors ISSCWR-7, Helsinki, Finland, 2015Conference paper (Refereed)
This paper presents steady state CFD simulation approach to supercritical water flow and heat transfer in a rod bundle with grid spacers. The current model was developed using the ANSYS Workbench 15.0 software (CFX solver) and first applied to supercritical water flow and heat transfer in circular tubes. The predicted wall temperature was in good agreement with the measured data. Next, a similar approach was used to investigate three dimensional vertical upward flow of water at supercritical pressure of about 25 MPa in a rod bundle with grid spacers. This work aimed into understanding thermal and hydrodynamic behaviour of fluid flow in complex geometry at specified boundary conditions. The modelled geometry consisted of a 1.5 m heated section in the rod bundle, a 0.2 m non-heated inlet section and five grid spacers. The computational mesh was prepared using two cell types. The sections of the rods with spacers were meshed using tetrahedral cells due to the complex geometry of the spacer, whereas sections without spacers were meshed with hexahedral cells resulting in a total of 28 million cells. Three different sets of experimental conditions were investigated in this study: a non-heated case and two heated cases. The non-heated case, A1, is calculated in order to extract the pressure drop across the rod bundle. For cases B1 and B2 a heat flux is applied on surface of the rods causing a rise in fluid temperature along the bundle. While the temperature of the fluid increases along with the flow heat deterioration effects can be present near the heated surface. Output from both B cases is temperature at pre-selected locations on the rods surfaces. CFD Investigation of Supercritical Water Flow and Heat Transfer in a Rod Bundle with Grid Spacers.
Place, publisher, year, edition, pages
Helsinki, Finland, 2015.
Research subject Energy Technology
IdentifiersURN: urn:nbn:se:kth:diva-163897OAI: oai:DiVA.org:kth-163897DiVA: diva2:802609
ISSCWR-7,March 15-18, 2015,Helsinki, Finland
FunderEU, FP7, Seventh Framework Programme, 249337
QC 201504202015-04-132015-04-132015-04-24Bibliographically approved