Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors
After a loss-of-coolant accident (LOCA) in a Pressurized Water Reactor (PWR), the temperature of the fuel elements cladding increases dramatically due to the heat produced by the fission products decay, which is not adequately removed by the vapor contained in the core. In order to avoid this shar...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Brazilian Radiation Protection Society (Sociedade Brasileira de Proteção Radiológica, SBPR)
2021-02-01
|
| Series: | Brazilian Journal of Radiation Sciences |
| Subjects: | |
| Online Access: | https://bjrs.org.br/revista/index.php/REVISTA/article/view/610 |
| _version_ | 1811234517253357568 |
|---|---|
| author | youssef morghi Amir Zacarias Mesquita |
| author_facet | youssef morghi Amir Zacarias Mesquita |
| author_sort | youssef morghi |
| collection | DOAJ |
| description |
After a loss-of-coolant accident (LOCA) in a Pressurized Water Reactor (PWR), the temperature of the fuel elements cladding increases dramatically due to the heat produced by the fission products decay, which is not adequately
removed by the vapor contained in the core. In order to avoid this sharp rise in temperature and consequent melting of the core, the Emergency Core Cooling System is activated. This system initially injects borated water from accumulator
tanks of the reactor through the inlet pipe (cold leg) and the outlet pipe (hot leg), or through the cold leg only, depending on the plant manufacturer. Some manufacturers add to this, direct injection into the upper plenum of the
reactor. The penetration of water into the reactor core is a complex thermofluidodynamic process because it involves the mixing of water with the vapor contained in the reactor, added to that generated in the contact of the water with the still hot surfaces in various geometries. In some critical locations, the vapor flowing in the opposite direction of the water can control the penetration of this into the core. This phenomenon is known as Countercurrent Flow Limitation (CCFL) or Flooding, and it are characterized by the control that a gas exerts in the liquid flow in the opposite direction.
This work presents a proposal to use a CFD to simulate the CCFL phenomenon. Numerical computing can provide important information and data that is difficult or expensive to measure or test experimentally. Given the importance of
computational science today, it can be considered a third and independent branch of science on an equal footing with the theoretical and experimental sciences.
|
| first_indexed | 2024-04-12T11:38:38Z |
| format | Article |
| id | doaj.art-6f63d9ae56ed463ca64f42f05eaaff5c |
| institution | Directory Open Access Journal |
| issn | 2319-0612 |
| language | English |
| last_indexed | 2024-04-12T11:38:38Z |
| publishDate | 2021-02-01 |
| publisher | Brazilian Radiation Protection Society (Sociedade Brasileira de Proteção Radiológica, SBPR) |
| record_format | Article |
| series | Brazilian Journal of Radiation Sciences |
| spelling | doaj.art-6f63d9ae56ed463ca64f42f05eaaff5c2022-12-22T03:34:46ZengBrazilian Radiation Protection Society (Sociedade Brasileira de Proteção Radiológica, SBPR)Brazilian Journal of Radiation Sciences2319-06122021-02-0183B10.15392/bjrs.v8i3B.610Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactorsyoussef morghi0Amir Zacarias MesquitaDoutorado em Ciência e Tecnologia das Radiações, Minerais e Materiais After a loss-of-coolant accident (LOCA) in a Pressurized Water Reactor (PWR), the temperature of the fuel elements cladding increases dramatically due to the heat produced by the fission products decay, which is not adequately removed by the vapor contained in the core. In order to avoid this sharp rise in temperature and consequent melting of the core, the Emergency Core Cooling System is activated. This system initially injects borated water from accumulator tanks of the reactor through the inlet pipe (cold leg) and the outlet pipe (hot leg), or through the cold leg only, depending on the plant manufacturer. Some manufacturers add to this, direct injection into the upper plenum of the reactor. The penetration of water into the reactor core is a complex thermofluidodynamic process because it involves the mixing of water with the vapor contained in the reactor, added to that generated in the contact of the water with the still hot surfaces in various geometries. In some critical locations, the vapor flowing in the opposite direction of the water can control the penetration of this into the core. This phenomenon is known as Countercurrent Flow Limitation (CCFL) or Flooding, and it are characterized by the control that a gas exerts in the liquid flow in the opposite direction. This work presents a proposal to use a CFD to simulate the CCFL phenomenon. Numerical computing can provide important information and data that is difficult or expensive to measure or test experimentally. Given the importance of computational science today, it can be considered a third and independent branch of science on an equal footing with the theoretical and experimental sciences. https://bjrs.org.br/revista/index.php/REVISTA/article/view/610Countercurrent Fow Limitation (CCFL)Computational fluid dynamicsLOCAPWR. |
| spellingShingle | youssef morghi Amir Zacarias Mesquita Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors Brazilian Journal of Radiation Sciences Countercurrent Fow Limitation (CCFL) Computational fluid dynamics LOCA PWR. |
| title | Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors |
| title_full | Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors |
| title_fullStr | Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors |
| title_full_unstemmed | Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors |
| title_short | Numerical Simulation Study on the Air/Water Counter- current Flow Limitation in Nuclear Reactors |
| title_sort | numerical simulation study on the air water counter current flow limitation in nuclear reactors |
| topic | Countercurrent Fow Limitation (CCFL) Computational fluid dynamics LOCA PWR. |
| url | https://bjrs.org.br/revista/index.php/REVISTA/article/view/610 |
| work_keys_str_mv | AT youssefmorghi numericalsimulationstudyontheairwatercountercurrentflowlimitationinnuclearreactors AT amirzacariasmesquita numericalsimulationstudyontheairwatercountercurrentflowlimitationinnuclearreactors |