The effect of spacer grid critical component on pressure drop under both single and two phase flow conditions
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B. Han
Abstract
As pressure drop is one of the most critical thermal hydraulic parameters for spacer grids the accurate estimation of it is the key to the design and development of spacer grids. Most of the available correlations for pressure drop do not contain any real geometrical parameters that characterize the grid effect. The main functions for spacer grid are structural support and flow mixing. Once the boundary sublayer near the rod bundle is disturbed, the liquid forms swirls or flow separation that affect pressure drop. However, under two phase flow conditions, due to the existence of steam bubble, the complexity for spacer grid are multiplied and pressure drop calculation becomes much more challenging. The influence of the dimple location, distance of mixing vane to the nearest strip, and the effect of inter-subchannel mixing among neighboring subchannels on pressure drop and downstream flow fields are analyzed in this paper. Based on this study, more detailed space grid geometry parameters are recommended for adding into the correlation when predicting pressure drop.
Kurzfassung
Da der Druckverlust einer der wichtigsten thermohydraulischen Parameter bei der Berechnung des Einflusses von Abstandshaltern auf die Strömung ist, ist seine korrekte Berechnung eine wesentliche Aufgabe beim Design und bei der Auslegung von Abstandshaltern. Viele der bestehenden Korrelationen berücksichtigen nicht die Detailgeometrie der Abstandshalter wie Form und Lage der Auflagenoppen, Abstände zwischen Mischungsfahnen. In diesem Beitrag wird der Einfluss dieser beiden geometrischen Daten, die das Stützverhalten und die Strömungsmischung entscheidend beeinflussen, detaillierter untersucht. Es wird eine Korrelation abgeleitet, die für Einphasen- und für Zweiphasenströmungen eine genauere Berechnung des Druckverlustes unter Berücksichtigung dieser geometrischen Eigenschaften ermöglicht.
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© 2016, Carl Hanser Verlag, München
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Challenges in reactor core thermal-hydraulics: subchannel analysis, CFD modeling and rod bundle CHF
- Technical Contributions/Fachbeiträge
- Subchannel analysis and correlation of the Rod Bundle Heat Transfer (RBHT) steam cooling experimental data
- CFD analysis on mixing effects of spacer grids with different dimples and sizes for advanced fuel assemblies
- An experimental investigation on dynamics and heat transfer associated with a single droplet impacting on a hot surface above the Leidenfrost point temperature
- Study on effects of mixing vane grids on coolant temperature distribution by subchannel analysis
- Reflood experiments in rod bundles with flow blockages due to clad ballooning
- The effect of spacer grid critical component on pressure drop under both single and two phase flow conditions
- Numerical method improvement for a subchannel code
- Numerical investigation on the characteristics of two-phase flow in fuel assemblies with spacer grid
- Effects of axial power shapes on CHF locations in a single tube and in rod bundle assemblies
- CFD evaluation on the thermohydraulic characteristics of tube support plates in steam generator
- Analysis of heat transfer under high heat flux nucleate boiling conditions
- Review of the correlation developments and a new concept based on mixing mechanism for heat transfer enhancement of spacer grids
- A comparison of the CFD simulation results in 5 × 5 sub-channels with mixing grids using different turbulence models
- Simulation of isothermal multi-phase fuel-coolant interaction using MPS method with GPU acceleration
- RELAP5 investigation on subchannel flow instability
Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Editorial
- Challenges in reactor core thermal-hydraulics: subchannel analysis, CFD modeling and rod bundle CHF
- Technical Contributions/Fachbeiträge
- Subchannel analysis and correlation of the Rod Bundle Heat Transfer (RBHT) steam cooling experimental data
- CFD analysis on mixing effects of spacer grids with different dimples and sizes for advanced fuel assemblies
- An experimental investigation on dynamics and heat transfer associated with a single droplet impacting on a hot surface above the Leidenfrost point temperature
- Study on effects of mixing vane grids on coolant temperature distribution by subchannel analysis
- Reflood experiments in rod bundles with flow blockages due to clad ballooning
- The effect of spacer grid critical component on pressure drop under both single and two phase flow conditions
- Numerical method improvement for a subchannel code
- Numerical investigation on the characteristics of two-phase flow in fuel assemblies with spacer grid
- Effects of axial power shapes on CHF locations in a single tube and in rod bundle assemblies
- CFD evaluation on the thermohydraulic characteristics of tube support plates in steam generator
- Analysis of heat transfer under high heat flux nucleate boiling conditions
- Review of the correlation developments and a new concept based on mixing mechanism for heat transfer enhancement of spacer grids
- A comparison of the CFD simulation results in 5 × 5 sub-channels with mixing grids using different turbulence models
- Simulation of isothermal multi-phase fuel-coolant interaction using MPS method with GPU acceleration
- RELAP5 investigation on subchannel flow instability
