Equilibrium based analytical model for estimation of pressure magnification during deflagration of hydrogen air mixtures
| Autor: | Sunil Ganju, Aditya Karanam, Rekha Singh, Pavan K. Sharma |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Flammable liquid
Nuclear and High Energy Physics Radiation Materials science Hydrogen 020209 energy Containment building chemistry.chemical_element 02 engineering and technology Mechanics law.invention Ignition system chemistry.chemical_compound Minimum ignition energy 020401 chemical engineering Nuclear Energy and Engineering chemistry law 0202 electrical engineering electronic engineering information engineering Deflagration General Materials Science 0204 chemical engineering Safety Risk Reliability and Quality |
| Zdroj: | Kerntechnik. 81:655-661 |
| ISSN: | 2195-8580 0932-3902 |
| DOI: | 10.3139/124.110589 |
| Popis: | During postulated accident sequences in nuclear reactors, hydrogen may get released from the core and form a flammable mixture in the surrounding containment structure. Ignition of such mixtures and the subsequent pressure rise are an imminent threat for safe and sustainable operation of nuclear reactors. Methods for evaluating post ignition characteristics are important for determining the design safety margins in such scenarios. This study presents two thermo-chemical models for determining the post ignition state. The first model is based on internal energy balance while the second model uses the concept of element potentials to minimize the free energy of the system with internal energy imposed as a constraint. Predictions from both the models have been compared against published data over a wide range of mixture compositions. Important differences in the regions close to flammability limits and for stoichiometric mixtures have been identified and explained. The equilibrium model has been validated for varied temperatures and pressures representative of initial conditions that may be present in the containment during accidents. Special emphasis has been given to the understanding of the role of dissociation and its effect on equilibrium pressure, temperature and species concentrations. |
| Databáze: | OpenAIRE |
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