### Abstract

Impact of injecting microbubbles on the thermal expansion due to the nuclear spallation reaction were examined numerically. Since the mercury density is higher than the density of solid wall, the interaction between mercury and solid wall must be taken into account. Our approach is to solve the momentum and energy conservation equations and the time development of elastic stress for both bubbly fluid and elastic solid. The Keller equation is employed to reproduce the nonlinear oscillation of bubble with considering the thermal dumping effect by the reduced order model. The continuum phase of liquid mercury is coupled with the discrete phase of microbubbles using the Euler-Lagrange method. As the results, the bubble cloud develops around the center of inertia of motion induced by the thermal expansion. The elasticity of the wall affects on the migration of the center of inertia away from the wall. The injection of microbubbles is effective to decrease the pressure rise due to thermal expansion for both rigid and elastic wall conditions when the void fraction of microbubbles is higher than the volume rate of thermal expansion of liquid mercury.

Original language | English |
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Title of host publication | Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011 |

Pages | 600-610 |

Number of pages | 11 |

Publication status | Published - Dec 1 2011 |

Externally published | Yes |

Event | 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011 - Kos, Greece Duration: Jun 20 2011 → Jun 22 2011 |

### Publication series

Name | Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011 |
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### Other

Other | 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011 |
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Country | Greece |

City | Kos |

Period | 6/20/11 → 6/22/11 |

### Fingerprint

### All Science Journal Classification (ASJC) codes

- Applied Mathematics
- Computational Mathematics

### Cite this

*Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011*(pp. 600-610). (Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011).

**Multi-scale analysis on cavitation damage and its mitigation for the spallation neutron source.** / Okita, Kohei; Ono, Kenji; Shu, Takagi; Matsumoto, Yoichiro.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011.*Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011, pp. 600-610, 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011, Kos, Greece, 6/20/11.

}

TY - GEN

T1 - Multi-scale analysis on cavitation damage and its mitigation for the spallation neutron source

AU - Okita, Kohei

AU - Ono, Kenji

AU - Shu, Takagi

AU - Matsumoto, Yoichiro

PY - 2011/12/1

Y1 - 2011/12/1

N2 - Impact of injecting microbubbles on the thermal expansion due to the nuclear spallation reaction were examined numerically. Since the mercury density is higher than the density of solid wall, the interaction between mercury and solid wall must be taken into account. Our approach is to solve the momentum and energy conservation equations and the time development of elastic stress for both bubbly fluid and elastic solid. The Keller equation is employed to reproduce the nonlinear oscillation of bubble with considering the thermal dumping effect by the reduced order model. The continuum phase of liquid mercury is coupled with the discrete phase of microbubbles using the Euler-Lagrange method. As the results, the bubble cloud develops around the center of inertia of motion induced by the thermal expansion. The elasticity of the wall affects on the migration of the center of inertia away from the wall. The injection of microbubbles is effective to decrease the pressure rise due to thermal expansion for both rigid and elastic wall conditions when the void fraction of microbubbles is higher than the volume rate of thermal expansion of liquid mercury.

AB - Impact of injecting microbubbles on the thermal expansion due to the nuclear spallation reaction were examined numerically. Since the mercury density is higher than the density of solid wall, the interaction between mercury and solid wall must be taken into account. Our approach is to solve the momentum and energy conservation equations and the time development of elastic stress for both bubbly fluid and elastic solid. The Keller equation is employed to reproduce the nonlinear oscillation of bubble with considering the thermal dumping effect by the reduced order model. The continuum phase of liquid mercury is coupled with the discrete phase of microbubbles using the Euler-Lagrange method. As the results, the bubble cloud develops around the center of inertia of motion induced by the thermal expansion. The elasticity of the wall affects on the migration of the center of inertia away from the wall. The injection of microbubbles is effective to decrease the pressure rise due to thermal expansion for both rigid and elastic wall conditions when the void fraction of microbubbles is higher than the volume rate of thermal expansion of liquid mercury.

UR - http://www.scopus.com/inward/record.url?scp=84857423071&partnerID=8YFLogxK

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M3 - Conference contribution

AN - SCOPUS:84857423071

SN - 9788489925786

T3 - Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011

SP - 600

EP - 610

BT - Proceedings of the 4th International Conference on Computational Methods for Coupled Problems in Science and Engineering, COUPLED PROBLEMS 2011

ER -