Static and Vibration Analysis of Axisymmetric Shells Using Mixed Finite Element

혼합 유한요소를 이용한 축대칭 쉘의 정.동적해석

  • 김진곤 (대구가톨릭대학교 기계자동차공학부) ;
  • 노병국 (대구가톨릭대학교 기계자동차공학부)
  • Published : 2003.06.01

Abstract

In this study, a new and efficient harmonic axisymmetric shell element for static and dynamic analysis Is proposed. The present element considering shear strain is based on a modified mixed variational principle in which the independent unknowns are only the Quantities prescribable at the shell edges. Unlike existing hybrid-mixed axisymmetric shell elements, the present element introduces additional nodeless degrees for displacement field Interpolation In order to enhance the numerical performance. The stress parameters are eliminated by the stationary condition and the nodeless degrees are condensed out by the Guyan reduction. Through several numerical examples, the hybrid-miked shell element with the additional nodeless degrees and the consistent stress parameters is shown to be efficient and yield very accurate results for static and vibration analysis.

본 연구에서는 축대칭 쉘구조물의 정동적해석을 효과적으로 수행할 수 있는 새로운 유한요소를 제안하였다. 본 유한요소는 축대칭 쉘의 전단변형률을 고려하였으며, 쉘의 경계에서 기술할 수 있는 변수들만으로 표현되는 효율적인 형태의 수정된 혼합 변분이론에 바탕하여 유한요소정식화를 수행하였다. 또한, 변위장에 대해 무절점 자유도를 추가적으로 도입하여 요소의 수치적 성능을 크게 향상시켰다 계산의 효율성을 위해, 요소정식화의 최종단계에서 정치조건으로부터 응력매개변수들을 제거하고, 동적축약을 통하여 무절점 자유도 성분들 또한 최종적인 유한요소방정식에서 제거되어짐으로써, 일반적인 변위기저 요소와 같은 크기의 유한요소방정식을 얻을 수 있다. 몇 가지 수치예제들에 대한 해석을 통하여, 무절점 자유도와 변위장에 일치하는 적절한 응력매개변수를 가지는 제안된 혼합 축대칭 쉘요소가 정동적해석에서 대단히 정확하고 효율적임을 확인할 수 있었다

Keywords

References

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