Numerical prediction of single-phase flow mixing characteristics in a 1/12th of the cross segment of a 54-rod bundle
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S. K. Verma
Abstract
Numerical simulations of selected subchannel tracer (Potassium Nitrate) based experiments have been performed to study the capabilities of state-of-the-art of Computational Fluid Dynamics (CFD) codes. A Reynolds stress model (RSM) has been selected as the primary turbulence model to be applied for the simulation case as it has been previously found reasonably accurate to predict flows inside rod bundles. As a comparison, the case is also simulated using a standard k-∊ turbulence model that is widely used in industry. Flow enters into the computational domain through the mass inflow at the three subchannel faces. Simulation results have been extracted at different locations of the mixing zone and downstream zone. The local mass fraction shows uniform mixing. In present investigation using the species transport model, includes the study of diffusion of two fluids (water and KNO3) to study its interaction and how mixing is enhanced. The species model is concerned with the transport of species with in this phase, where it is experimentally found that our species are completely miscible. The effect of the applied turbulence model is nearly negligible just before the outlet plane because the distributions look like almost identical and the flow is fully developed. On the other hand, quantitatively the dimensionless mixing scalar distributions change noticeably, which is visible in the different scale of the colour bars.
Kurzfassung
Numerische Simulationen ausgewählter Unterkanal Experimente mit Tracern (Kaliumnitrat) wurden durchgeführt, um den Stand der Technik der Computational Fluid Dynamics (CFD)-Codes zu untersuchen. Ein Reynolds-Spannungsmodell (RSM) wurde als primäres Turbulenzmodell für den Simulationsfall ausgewählt, da es als ziemlich genau für die Vorhersage von Strömungen in Stabbündeln gilt. Zum Vergleich wird der Fall auch mit einem in der Industrie weit verbreiteten Standard-Turbulenzmodell k-∊ simuliert. Die Strömung tritt durch den Masseneinstrom an den drei Unterkanalflächen in den Berechnungsbereich ein. Die Simulationsergebnisse wurden an verschiedenen Stellen der Mischzone und der nachgelagerten Zone extrahiert. Die lokale Massenfraktion zeigt eine gleichmäßige Vermischung. In der vorliegenden Untersuchung mit Hilfe des Transportmodells verschiedener Arten wird die Diffusion von zwei Flüssigkeiten (Wasser und KNO3) berücksichtigt, um die Interaktionen zu untersuchen und um herauszufinden, wie die Mischung verbessert werden kann. Das Modell der verschiedenen Arten beschäftigt sich mit dem Transport von Arten in einer Phase, wenn experimentell festgestellt wurde, dass diese Arten vollständig mischbar sind. Die Effektivität des angewandten Turbulenzmodells ist kurz vor der Austrittsebene nahezu vernachlässigbar, da die Verteilungen nahezu identisch aussehen und die Strömung voll entwickelt ist. Andererseits ändern sich die dimensionslosen Mischskalaverteilungen quantitativ deutlich, was in der unterschiedlichen Skala der Farbbalken sichtbar ist.
References
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© 2019, Carl Hanser Verlag, München
Articles in the same Issue
- Contents/Inhalt
- Contents
- Technical Contributions/Fachbeiträge
- Revision of a CHF correlation for PWR under low pressure conditions with only dimensionless parameters as independent variables
- Experimental study on transient flow fluctuation characteristics in a 3 × 3 rod bundle under rolling condition
- The core shroud leakage analysis and study for Kuosheng nuclear power plant
- Coupling simulation of neutron kinetics core model with CFD of IPWR steam line break accident
- Numerical prediction of single-phase flow mixing characteristics in a 1/12th of the cross segment of a 54-rod bundle
- 10.3139/124.110984
- Control rod material effect on safety parameters of research reactors
Articles in the same Issue
- Contents/Inhalt
- Contents
- Technical Contributions/Fachbeiträge
- Revision of a CHF correlation for PWR under low pressure conditions with only dimensionless parameters as independent variables
- Experimental study on transient flow fluctuation characteristics in a 3 × 3 rod bundle under rolling condition
- The core shroud leakage analysis and study for Kuosheng nuclear power plant
- Coupling simulation of neutron kinetics core model with CFD of IPWR steam line break accident
- Numerical prediction of single-phase flow mixing characteristics in a 1/12th of the cross segment of a 54-rod bundle
- 10.3139/124.110984
- Control rod material effect on safety parameters of research reactors
