Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
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Analytical Study on Equivalent Shear Modulus according to Shape of Egg-box Core

에그-박스 코어 형상 변화에 따른 등가 전단 탄성계수 수치 해석 연구

  • Lee, SangYoun (Advanced Propulsion Technology Center, Agency for Defence Development) ;
  • Yun, Su-Jin (Advanced Propulsion Technology Center, Agency for Defence Development) ;
  • Park, DongChang (Advanced Propulsion Technology Center, Agency for Defence Development) ;
  • Hwang, Kiyoung (Advanced Propulsion Technology Center, Agency for Defence Development)
  • Received : 2012.11.30
  • Accepted : 2014.03.06
  • Published : 2014.04.01
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Abstract

The sandwich shell with Egg-box core has been used for the combustion chamber case of air breathing propulsion system. The alteration on pitch length and thickness of Egg-box core was required to be lighter and save manufacturing time and cost of combustion chamber case. In this paper, the finite element analysis method which simulated bending test was used to predict the equivalent shear modulus which affect structural stability of sandwich shell in short time. The result of FE calculation on sandwich panel with homogeneous material, H130-foam core, showed a good agreement with the values available in the reference. The equivalent shear modulus of Egg-box core according to the variation of pitch length and thickness can be obtained.

본 논문에서 다루고 있는 에그-박스 코어는 공기 흡입식 추진기관의 연소실 케이스로 사용되고 있다. 무게의 경량화 및 제작 비용/시간을 절감하기 위한 목적으로 에그-박스 코어의 피치 길이 및 두께 변경의 필요성이 대두되었다. 짧은 시간 내에 에그-박스 코어 변경에 있어 연소실 케이스의 구조 안정성에 영향을 미치는 등가 전단 탄성계수의 특성을 파악할 수 있는 방법으로 굽힘 시험을 모사한 유한요소해석을 이용하였다. 등방성 재료인 H130-폼 코어를 가지는 샌드위치 판넬에 대한 유한요소해석을 수행하여 얻은 전단 탄성계수 값이 참고문헌에서 주어진 값과 거의 일치함을 확인하였다. 에그-박스 코어의 피치 길이와 두께 변화에 따른 등가 전단 탄성계수 변화를 확인할 수 있었다.

Keywords

References

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