[항공] Computational Study on Unsteady Mechanism of Spinning Detonations

1. 제목 : Computational Study on Unsteady Mechanism of Spinning Detonations

2. 일시 : 2008년 10월 23일(목) 15:00-16:00

3. 장소 : 서울대학교 301동 117호

4. 연사 : Prof. Akiko Matsuo(Department of Mechanical Engineering, Keio University, Japan)

5. 내용 :
Detonations are supersonic flow phenomena with leading shock waves that ignite premixed gas. The structure and properties of detonation have been investigated by many researchers using experimental, theoretical, and numerical approaches. Although detonation has been experimentally shown to propagate in both longitudinal and transverse directions with unstable 3D structure, the detailed structure of detonation has not been become clear because of difficulty of 3D visualization by experimental devices. Here, spinning detonations propagating in a circular tube were numerically investigated with a one-step irreversible reaction model governed by Arrhenius kinetics. The time evolution of the simulation results was utilized to reveal the propagation mechanism of single-headed spinning detonation. The track angle of soot record on the tube wall was numerically reproduced with various levels of activation energy. The maximum pressure histories of the shock front on the tube wall showed stable pitch at Ea=10, periodical unstable pitch at Ea=20 and 27 and unstable pitch consisting of stable, periodical unstable and weak modes at Ea=35, respectively. The shock front shapes and the pressure profiles on the tube wall clarified the mechanisms of these stable and unstable modes. A series of simulations of spinning detonations clarified that the unsteady mechanism behind the shock front depending on the activation energy.

6. 약력 :
1993 Ph.D, Nagoya University, Department of Aeronautical Engineering
1994 JSPS Fellow (PD), The Institute of Space and Astronautical Science
1995 Research Associate, Keio University, Department of Mechanical Engineering
1997 Assistant Professor, Keio University , Department of Mechanical Engineering
2001 Associate Professor, Keio University , Department of Mechanical Engineering
2008 Professor, Keio University , Department of Mechanical Engineering

7. 문 의 : 기계항공공학부 정인석 교수(☏ 880-7387)