• Title/Summary/Keyword: 유동방향 변환 감쇠

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Study on Acoustic Attenuation due to Particles and Flow Turning in Rocket Motors (고체 입자와 유동방향 변환에 의한 로켓 모터 내 음향 감쇠에 대한 고찰)

  • Kim, Taejin;Sung, Hong-Gye;Seo, Seonghyeon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.9
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    • pp.838-844
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    • 2015
  • This paper includes summarization and analysis of previous research results on acoustic attenuation due to particles and flow turning in rocket motors among various damping parameters. Particle damping is the most effective mechanism in suppressing high-frequency combustion instabilities occurring in rocket combustion chambers, which is dependent on the size and the mass fraction of particles. Relatively weak attenuation by flow turning compared to particle damping depends on the geometry of propellant and a combustion chamber. Pumping driving effects need to be taken into account when realizing vorticity generation on the propellant surface. However, its driving effects become cancelled out by flow turning loss when the propellant geometry is cylindrical.

Linear Stability Analysis for Combustion Instability in Solid Propellant Rocket (고체추진 로켓의 선형 안정성 요소에 대한 연구)

  • Kim, Hakchul;Kim, Junseong;Moon, Heejang;Sung, Honggye;Lee, Hunki;Ohm, Wonsuk;Lee, Dohyung
    • Journal of the Korean Society of Propulsion Engineers
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    • v.17 no.5
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    • pp.27-36
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    • 2013
  • Linear stability analysis for combustion instability within a cylindrical port of solid rocket motor has been conducted. The analysis of acoustic energy has been performed by a commercial COMSOL code to obtain the mode function associated to each acoustic mode prior to the calculation of stability alpha. An instability diagnosis based on the linear stability analysis of Culick is performed where special interests have been focused on 5 stability factors(alpha) such as pressure coupling, nozzle damping, particle damping and additionally, flow turning effect and viscous damping to take into account the flow and viscosity effect near the fuel surface. The instability decay characteristics depending on the particle size is also analyzed.