Validation of the hem and moody critical flow models in polca-T
2016 (English)In: Physics of Reactors 2016, PHYSOR 2016: Unifying Theory and Experiments in the 21st Century, American Nuclear Society, 2016, 2724-2732 p.Conference paper (Refereed)
The Homogeneous Equilibrium Model (HEM) and Moody critical flow models implemented in POLCA-T are validated against the Marviken experiments, which is necessary for qualification of the code for simulations of the hypothetical loss-of-coolant accident. Seven Marviken cases covering a range of initial conditions are simulated and the POLCA-T results are compared to the experimental data and to other similar codes including GOBLIN, RELAP5 and TRACE. Sensitivity studies are performed with respect to nodalisation and initial conditions. The HEM model predicts the break flow accurately with an uncertainty mostly below 20 %. The largest uncertainties are found for small exhaust pipe diameter and initial conditions far from saturation. The results could be improved by finer nodalisation and an extrapolation of the initial temperature profile inside the exhaust pipe. The Moody model is conservative in the 2-phase region, where it overpredicts the break flow as it should. The overprediction is smaller compared GOBLIN, so the conservatism is reduced.
Place, publisher, year, edition, pages
American Nuclear Society, 2016. 2724-2732 p.
Critical-flow, HEM, Marviken, Moody, POLCA-T, Critical flow, Critical flow models, Homogeneous equilibrium models, Initial temperatures, Sensitivity studies, Loss of coolant accidents
IdentifiersURN: urn:nbn:se:kth:diva-201998ScopusID: 2-s2.0-84992048117ISBN: 9781510825734 OAI: oai:DiVA.org:kth-201998DiVA: diva2:1077053
Physics of Reactors 2016: Unifying Theory and Experiments in the 21st Century, PHYSOR 2016, 1 May 2016 through 5 May 2016
QC 201702242017-02-242017-02-242017-02-24Bibliographically approved