Impact of population balance model on subcooled flow boiling simulation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21340%2F23%3A00368673" target="_blank" >RIV/68407700:21340/23:00368673 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.13182/NURETH20-40085" target="_blank" >https://doi.org/10.13182/NURETH20-40085</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.13182/NURETH20-40085" target="_blank" >10.13182/NURETH20-40085</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Impact of population balance model on subcooled flow boiling simulation

Popis výsledku v původním jazyce

This paper presents two modifications of Eulerian CFD (Computational Fluid Dynamics) model to predict subcooled boiling flows in the DEBORA experiment, the conditions of Freon-R12 corresponding to those in PWRs (Pressurized Water Reactors). Literature study reveals that the experimental data, which were used for CFD validation, were limited to low void fraction cases (< 0.3), and the cases with high void were not presented. This work focuses primarily on having good agreement with these cases of high void fraction, which is achieved by modifying the lift force coefficients in the zero-closure model developed by Baglietto’s group. In addition, low void fraction cases were also evaluated in order to show the applicability of our model to wide range of void fraction. Different combinations of closure relations were tested to conform the results of the DEBORA experiment. The first Model is built on a complex transport equation for interfacial area concentration with a simple algebraic equation for bubble diameter calculation. The second one includes a population balance model (PBM) for bubble diameter calculation, and also a new modification bubble departure diameter model is presented. A homogeneous PBM is introduced to accurately predict large size distribution of the dispersed vapor bubbles. To better implement PBM, sensitivity analyses need to be performed to select the suitable coalescence and breakage models and factors. Different correlations for nucleation site density are used in both Models.

Název v anglickém jazyce

Impact of population balance model on subcooled flow boiling simulation

Popis výsledku anglicky

This paper presents two modifications of Eulerian CFD (Computational Fluid Dynamics) model to predict subcooled boiling flows in the DEBORA experiment, the conditions of Freon-R12 corresponding to those in PWRs (Pressurized Water Reactors). Literature study reveals that the experimental data, which were used for CFD validation, were limited to low void fraction cases (< 0.3), and the cases with high void were not presented. This work focuses primarily on having good agreement with these cases of high void fraction, which is achieved by modifying the lift force coefficients in the zero-closure model developed by Baglietto’s group. In addition, low void fraction cases were also evaluated in order to show the applicability of our model to wide range of void fraction. Different combinations of closure relations were tested to conform the results of the DEBORA experiment. The first Model is built on a complex transport equation for interfacial area concentration with a simple algebraic equation for bubble diameter calculation. The second one includes a population balance model (PBM) for bubble diameter calculation, and also a new modification bubble departure diameter model is presented. A homogeneous PBM is introduced to accurately predict large size distribution of the dispersed vapor bubbles. To better implement PBM, sensitivity analyses need to be performed to select the suitable coalescence and breakage models and factors. Different correlations for nucleation site density are used in both Models.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

10700 - Other natural sciences

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Proceedings of the 20th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-20)

ISBN

978-0-89448-793-4

ISSN

—

e-ISSN

—

Počet stran výsledku

13

Strana od-do

212-224

Název nakladatele

American Nuclear Society, Inc.

Místo vydání

Illinois

Místo konání akce

Washington DC

Datum konání akce

20. 8. 2023

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

—