Development of scalable empirical closures for self-leveling of particulate debris bed
2014 (English)In: Proceedings of ICAPP 201, Paper 14330, American Nuclear Society, 2014, 14330- p.Conference paper (Refereed)
Melt fragmentation, quenching and long term coolability in a deep pool of water under reactor vessel is employed as a severe accident mitigation strategy in several designs of light water reactors. Geometrical configuration of the debris bed is one of the factors which define if the decay heat can be removed from the debris bed by natural circulation. A bed can be coolable if spread uniformly, while the same debris forming a tall mound-shape debris bed can be non-coolable. Two-phase flow inside the bed serves as a source of mechanical energy which can move debris, thus flatten and gradually reduce the height of the debris bed. There is a competition between the time scales for (i) reaching a coolable configuration of the bed by such “self-leveling” phenomenon, and (ii) onset of dryout and re-melting of the debris. In the previous work we have demonstrated that the rate of particulate debris spreading is determined by local (i) gas velocity, and (ii) slope angle of the bed. The goal of this work is to obtain a dependency of particle motion rate on local slope angle and gas velocity expressed in non-dimensional variables, universal for particles of different shapes, sizes and materials. Such scaling approach is proposed in this work and validated against experimental data.
Place, publisher, year, edition, pages
American Nuclear Society, 2014. 14330- p.
Severe accident, debris bed, particle spreading, self-leveling, accident mitigation, closures
Allvarlig olycka, partikel hög, partikelspridning, självutjämnande, mildring av olycka, empiriska förslutningar
Other Physics Topics
Research subject Energy Technology; Physics
IdentifiersURN: urn:nbn:se:kth:diva-165099ScopusID: 2-s2.0-84907068899ISBN: 978-0-89448-460-5OAI: oai:DiVA.org:kth-165099DiVA: diva2:807357
International Congress on Advances in Nuclear Power Plants,Charlotte, North Carolina April 6-9, 2014
See more information on http://www.ans.org/store/i_700385
QC 201504272015-04-232015-04-232015-04-27Bibliographically approved