• Nuclear Engineering and Technology
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• 제38권7호
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• pp.689-696
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• 2006

For a perforated plate, it is challenging to develop a finite element model due to the necessity of the fine meshing of the plate, especially if it is submerged in fluid. This necessitates the use of a solid plate with equivalent material properties. Unfortunately, the effective elastic constants suggested by the ASME code are deemed not valid for a modal analysis. Therefore, in this study the equivalent material properties of a perforated plate are suggested by performing several finite element analyses with respect to the ligament efficiencies.

• Journal of Mechanical Science and Technology
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• 제20권9호
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• pp.1323-1338
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• 2006

An analytical method to estimate the coupled frequencies of the circular plate submerged in fluid is developed using the finite Fourier-Bessel series expansion and Rayleigh-Ritz method. To verify the validity of the analytical method developed, finite element method is used and the frequency comparisons between them are found to be in good agreement. For the perforated plate submerged in fluid, it is almost impossible to develop a finite element model due to the necessity of the fine meshing of the plate and the fluid at the same time. This necessitates the use of solid plate with equivalent material properties. Unfortunately the effective elastic constants suggested by the ASME code are found to be not valid for the modal analysis. Therefore in this study the equivalent material properties of perforated plate are suggested by performing several finite element analyses with respect to the ligament efficiencies.

• 한국압력기기공학회 논문집
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• 제15권1호
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• pp.8-17
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• 2019

Perforated plates are used for the steam generator tube-sheet and the Reactor Vessel Closure Head in the Nuclear Power Plant. The ASME code, Section III Appendix A-8000, addresses the analysis of perforated plates, however, this analysis is only limited to the flat plate with a triangular perforation pattern. Based on the concept of the effective elastic constants, simulation of flat and spherical perforated plates and their equivalent solid plates were carried out using Finite Element Analysis (FEA). The isotropic material properties of the perforated plate were replaced with anisotropic material properties of the equivalent solid plate and subjected to the same loading conditions. The generated curves of effective elastic constants vs ligament efficiency for the flat perforated plate were in agreement with the design curve provided by ASME code. With this result, a plate with spherical curvature having perforations can be conveniently analyzed with equivalent elastic modulus and equivalent Poisson's ratio.

• 한국전산구조공학회논문집
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• 제19권3호
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• pp.247-258
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• 2006

물에 잠긴 다공 원통형 쉘의 경우 물에 잠긴 상태로 유한요소해석을 하기에는 거의 불가능하므로 등가물성치를 사용하여야 한다. 다공 평판의 경우 이에 대한 등가물성치를 ASME 코드에서 제시하고 있지만, 다공 원통형 쉘의 등가물성치에 대한 연구는 아직까지 수행된 적이 없다. 따라서 본 연구에서는 유한요소해석을 이용하여 다공 원통형 쉘의 동적 해석에 이용할 수 있는 등가물성치를 제안하였고 그 타당성을 검증하였다.

• 청정기술
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• 제8권1호
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• pp.45-51
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• 2002

회전 무화형 도장기기의 고효율화를 위한 기초 연구로서 도장기기 회전 디스크의 형태에 따른 도장기기의 성능을 실험적으로 고찰하였다. 본 연구에서는 도료의 무화가 선상 무화가 유지되도록 도장기기 디스크의 빗살무늬 형상을 설계하였다. 최적설계에 따라 제작된 도장 기기의 도장 성능시험을 통해 도착효율 및 도막특성을 실험적으로 관찰하였고, 기존의 도장기기 성능 시험결과와 비교 분석하였으며, 회전디스크의 빗살무늬 형태가 도착효율 및 도막 특성에 미치는 영향을 규명하였다.