Estimating steady state and transient characteristics of molten salt natural circulation loop using CFD
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J. Y. Kudariyawar
Abstract
The steady state and transient characteristics of a molten salt natural circulation loop (NCL) are obtained by 3D CFD simulations. The working fluid is a mixture of NaNO3 and KNO3 in 60:40 ratio. Simulation is performed using PHOENICS CFD software. The computational domain is discretized by a body fitted grid generated using in-built mesh generator. The CFD model includes primary side. Primary side fluid is subjected to heat addition in heater section, heat loss to ambient (in piping connecting heater and cooler) and to secondary side (in cooler section). Reynolds Averaged Navier Stokes equations are solved along with the standard k-∊ turbulence model. Validation of the model is done by comparing the computed steady state Reynolds number with that predicted by various correlations proposed previously. Transient simulations were carried out to study the flow initiations transients for different heater powers and different configurations. Similarly the “power raising” transient is computed and compared with in-house experimental data. It is found that, using detailed information obtained from 3D transient CFD simulations, it is possible to understand the physics of oscillatory flow patterns obtained in the loop under certain conditions.
Kurzfassung
Die stationären und transienten Eigenschaften von Salzschmelze im Naturumlauf wurden mit Hilfe von 3D-CFD-Simulationen bestimmt. Die Salzschmelze ist eine Mischung aus NaNO3 und KNO3 im Verhältnis 60:40. Die Simulation wurde mit Hilfe der PHOENICS-CFD-Software durchgeführt. Das CFD-Modell beinhaltet den Primärseitenbereich. Im Primärseitenbereich wird die Flüssigkeit im Heizabschnitt zusätzlich erwärmt und gibt in anderen Bereichen Wärme an die Umgebung und an den Sekundärseitenbereich ab. Reynolds-gemittelte Navier-Stokes-Gleichungen wurden zusammen mit dem Standard k-∊ Turbulenzmodell gelöst. Die Validierung des Modells wird durchgeführt durch Vergleich der berechneten Reynolds-Zahl im stationären Zustand mit der Reynolds-Zahl, die vorher durch verschiedene, vorgeschlagene Korrelationen vorhergesagt wurde. Transiente Simulationen wurden durchgeführt um die Strömungstransienten für verschiedene Heizleistungen und unterschiedliche Konfigurationen zu untersuchen. Dabei zeigte sich, dass es bei Anwendung der aus den 3D-transienten CFD-Simulationen erhaltenen detaillierten Information möglich ist die Physik des unidirektionalen und bi-direktionalen oszillatorischen Strömungsverhaltens zu verstehen.
References
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© 2015, Carl Hanser Verlag, München
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Evaluation of advanced displacement cross-sections for the major EUROFER constituents based on an atomistic modelling approach
- Tarapur atomic power station: analysis of station blackout scenario
- Estimating steady state and transient characteristics of molten salt natural circulation loop using CFD
- Thermal hydraulic analysis of ETRR-2 using RELAP5 code
- Transient performance during stopping the research reactor primary loop pump
- Neutronic performance calculations with alternative fluids in a hybrid reactor by using the Monte Carlo method
- A study on the criticality of modified neutron transport equation by using alternative scattering phase functions
- Production cross–section calculations of medical 32P, 117Sn, 153Sm and 186,188Re radionuclides used in bone pain palliation treatment
- Study on carbonated hydroxyapatite as a thermoluminescence dosimeter
- Social impact theory based modeling for security analysis in the nuclear fuel cycle
- Analysis of a homogenous and heterogeneous stylized half core of a CANDU reactor
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Evaluation of advanced displacement cross-sections for the major EUROFER constituents based on an atomistic modelling approach
- Tarapur atomic power station: analysis of station blackout scenario
- Estimating steady state and transient characteristics of molten salt natural circulation loop using CFD
- Thermal hydraulic analysis of ETRR-2 using RELAP5 code
- Transient performance during stopping the research reactor primary loop pump
- Neutronic performance calculations with alternative fluids in a hybrid reactor by using the Monte Carlo method
- A study on the criticality of modified neutron transport equation by using alternative scattering phase functions
- Production cross–section calculations of medical 32P, 117Sn, 153Sm and 186,188Re radionuclides used in bone pain palliation treatment
- Study on carbonated hydroxyapatite as a thermoluminescence dosimeter
- Social impact theory based modeling for security analysis in the nuclear fuel cycle
- Analysis of a homogenous and heterogeneous stylized half core of a CANDU reactor
