Experimental investigations on control of flow instability in single-phase natural circulation loop
-
K. Bodkha
, N. Kumar and P. K. Vijayan
Abstract
Natural circulation systems offer simplicity, enhanced safety and reliability and thus are advantageous over their forced circulation counterpart. However, natural circulation is susceptible to flow instabilities. These instabilities are undesirable for various reasons. Literature suggests the use of orifices at the inlet to suppress instability. However, orificing introduces pressure drop which limits the flow rate and hence the heat carrying capacity of the fluid. In the present study, investigations have been carried out with different mechanical gadgets to control the natural circulation flow instabilities. Extensive experiments have been carried out in a single-phase rectangular natural circulation loop to study the effect of these mechanical gadgets on instability. The paper brings out the results of experimental investigations carried out on the role of mechanical gadgets in controlling instability.
Kurzfassung
Naturumlaufsysteme bieten Einfachheit, erhöhte Sicherheit und Zuverlässigkeit und sind deshalb von Vorteil gegenüber Systemen mit erzwungenem Umlauf. Der Naturumlauf ist jedoch anfällig gegenüber Strömungsinstabilitäten. Solche Instabilitäten sind aus verschiedenen Gründen unerwünscht. In der Literatur wird die Verwendung von Öffnungen am Einlass zur Unterdrückung von Instabilitäten beschrieben. Öffnungen bewirken jedoch einen Druckabfall, der die Strömungsgeschwindigkeit begrenzt und damit die Wärmeleitfähigkeit. In dem vorliegenden Arbeit wurden Untersuchungen durchgeführt mit verschiedenen mechanischen Vorrichtungen zur Kontrolle der Strömungsinstabilitäten beim Naturumlauf. Umfangreiche Experimente wurden in einem einphasigen rechteckigen Naturumlaufsystem durchgeführt, um die Wirkung dieser mechanischen Vorrichtungen auf die Instabilitäten zu untersuchen. Der Beitrag präsentiert die Ergebnisse experimenteller Untersuchungen mit mechanischen Vorrichtungen zur Kontrolle von Instabilitäten.
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Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries
- Technical Contributions/Fachbeiträge
- Chemistry aspects of the source term formation for a severe accident in a CANDU type reactor
- Analytical study on degraded core quenching
- Experimental investigations on control of flow instability in single-phase natural circulation loop
- Burnup calculations using serpent code in accelerator driven thorium reactors
- Investigation of neutronic effects in structural material of a hybrid reactor by using the MCNPX Monte Carlo transport code
- Nuclear aspects and cyclotron production of the positron emitter 55Co
- Calculation of age-dependent effective doses for external exposure using the MCNP code
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- A numerical method for resonance integral calculations
- Computational modeling of monoenergetic neutral particle inverse transport problems in slab geometry
- Effects on criticality of selected scattering phase functions in neutron transport equation using the Chebyshev approximation
- U1 and P1 approximations to neutron transport equation for diffusion length calculation
- Technical Notes/Technische Mitteilungen
- TN approximation for the critical size of one-speed neutrons in a slab with anisotropic scattering
- Albedo and constant source problems for extremely anisotropic scattering