• 한국구조물진단유지관리공학회 논문집
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• 제6권3호
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• pp.97-102
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• 2002

Two dimensional Analysis has been applied to most of tunnel lining design in these days. Two dimensional analysis uses beam or curved beam element for finite element method. But because the behaviors of tunnel concrete lining structure is near to shell, it is required to model the tunnel lining as shell structure for safety design of tunnel lining structure. In this paper, two dimensional analysis by beam element and the three dimensional analysis by shell element of tunnel concrete lining are studied, in which 3 type of tunnel lining and lateral pressure factors are considered. As results of the study, three dimensional analyses of the behavior of tunnel concrete lining structure considering lateral pressure factor shows that the moment of three dimensional analysis is greater than those of two dimensional analysis. The results shows that three dimensional analysis is necessary for safety design of tunnel lining.

• 대한기계학회논문집
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• 제19권10호
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• pp.2617-2629
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• 1995

The flow through a centrifugal compressor rotor was calculated using the quasi-3-dimensional and fully 3-dimensional Navier-Stokes solution methods. The calculated results, obtained during the development of the computer codes for both methods are discussed. In the inviscid quasi 3-dimensional analysis, stream function formulation was used for the blade to blade (B-B) plane calculations, and the streamline curvature method was used for the meridional (H-S) plane calculations. In the viscous 3-dimensional flow analysis, a control volume method based on a general rotating curvilinear coordinate system was used to solve the time-averaged Navier-Stokes equations, and a standard k-.epsilon. model was used to obtain eddy viscosity. The quasi-3-dimensional analysis reasonably predicts the pressure distributions and requires much less computation time in the region where viscous effects are not strong; however, it fails to predict velocity field and loss mechanism through the impeller passage. The viscous 3-dimensional flow analysis shows reasonable pressure distributions and typical jet-wake flow field through the impeller passage. Secondary flow and total pressure distributions on cross-sectional planes explain the loss mechanisms through the impeller.

• Journal of Ship and Ocean Technology
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• 제3권3호
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• pp.13-24
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• 1999

In this paper, a 2-dimensional novel beam element is developed and a method to replace the 3-dimensional analysis with 2-dimensional analysis is proposed. The developed novel beam element named rigid-ended beam element can consider the effect of three kinds of span points within one element, which was impossible in modeling with the ordinary beam element. Calculated results for the portal frame using the rigid-ended beam element agree with the results using membrane element. And also, the proposed simplified 3- dimensional analysis method which includes two step analysis using influence coefficients shows good accuracy. Structural analysis using the rigid-ended beam element and the simplified 3-dimensional method is revealed to have good computing efficiency due to unnecessity of the elements corresponding to the brackets and simplification of 3-dimensional analysis.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권10호
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• pp.545-553
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• 2002

This paper is about the analysis of 3-dimensional magnetic field distribution in CPM(Convergence Purity Magnet) considering magnetization vector and the optimum design of CPM. The magnetization vector of CPM is obtained using 2-dimensional magnetization FEA(Finite Element Analysis) coupled with Priesach model. Using this magnetization vector of CPM, we analysed the 2-dimensional and 3-dimensional magnetostatic field of CPM and know that these analysis results are not equal. From experimental result, we know that the 3-dimensional analysis is accurate because the magnetic field distribution in CPM cannot be considered correctly by 2-dimensional analysis because of the shape of CPM. Finally, the optimum designing of CPM which control accurately the electron beam deflection in CRT(Cathode Ray Tube) was possible using 3-dimensional magnetic field analysis result.

• 산업기술연구
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• 제1권
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• pp.17-25
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• 1981

Past research has concentrated on refining two-dimensional analysis techniques. Rather extensive comparisons of various two-dimensional methods have been made. This paper described a general three-dimensional method of analysis by which any geometrical condition and any c, phi soil can be analyzed. The results are as follows; 1. Factors of safety computed for 3-dimensional geometry differ considerably from ordinary 2-dimensional factors of safety. 2. 3-dimensional factors of safety are generally much higher than 2-dimensional factors of safety. However, situations appear to exist where the 3-dimensional factor of safety can be lower than the 2-dimensional factor of safety. 3. The F3/F2 ration appears to be quite sensitive to c, phi and to the slope.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.801-810
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• 2010

Until now, design of Earth Retaining is practiced by 2nd dimensional analysis for convenience of analysis and time saving. However, the construction field is 3rd dimension, in this study, practised the 3rd dimensional analysis which can reflect the field condition more exactly the scope of earth retaining wall, and researched about the effective and economical way of design, compared and reviewed with the results, by practising both the 2nd and 3rd dimensional analysis. existing 2nd dimension. the depth of excavation, depth of embedded and soil condition. As result, under the whole conditions, more displacement came to appear to the value as result of 3rd dimensional analysis more than the result of 2nd dimensional analysis. Accordingly, the displacement by the 2nd dimension analysis is underestimated. Moreover, results of 2nd and 3rd dimensional analysis, there is no difference at displacement, when the depth of embedded is 0.5H, 1.0H and 1.5H, but Displacement of 1.5H is smaller than 0.5H, 1.0H. That is, the bigger the depth of embedded becomes, the displacement of Earth Retaining Wall appeared smaller. The displacement of earth retaining wall according to depth of excavation appeared bigger, when the depth of excavation is increased. In the meantime, when the soil condition is different, in the 2nd dimensional analysis, the displacement appeared biggest, in case of the clay layer, but in the 3rd dimensional analysis, in the beginning of excavating, the displacement of earth retaining wall appeared bigger in case of clay layer, but as excavating is in progress, the displacement of both compound soil layer and sand layer appeared big.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.181-185
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• 2010

Until now, design of Earth Retaining is practiced by 2 dimensional analysis for convenience of analysis and time saving. However, the construction field is 3 dimension, in this study, practised the 3 dimensional analysis which can reflect the field condition more exactly the scope of earth retaining wall, and researched about the effective and economical way of design, compared and reviewed with the results, by practising both the 2 and 3 dimensional analysis. existing 2 dimension. the depth of excavation, depth of embedded and soil condition. As result, under the whole conditions, more displacement came to appear to the value as result of 3 dimensional analysis more than the result of 2nd dimensional analysis. Accordingly, the displacement by the 2 dimension analysis is underestimated. Moreover, results of 2 and 3 dimensional analysis, there is no difference at displacement, when the depth of embedded is 0.5H and 1.0H, but Displacement of 1.5H is smaller than 0.5H, 1.0H. That is, the bigger the depth of embedded becomes, the displacement of Earth Retaining Wall appeared smaller. The displacement of earth retaining wall according to depth of excavation appeared bigger, when the depth of excavation is increased. In the meantime, when the soil condition is different, in the 2 dimensional analysis, the displacement appeared biggest, in case of the clay layer, but in the 3 dimensional analysis, in the beginning of excavating, the displacement of earth retaining wall appeared bigger in case of clay layer, but as excavating is in progress, the displacement of both compound soil layer and sand layer appeared big.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.18-24
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• 2010

철도차량의 동특성 해석을 위한 기존의 연구는 대부분 2차원 접촉해석에 근거한 근사해법에 의존해 왔다. 최근에 휠-접촉해석에 대한 정확한 해를 구하기 위해 3차원적 접근방법이 제시되고 있지만, 계산시간의 과다로 인해 실제 시뮬레이션 적용에는 효과적이지 못했다. 본 연구의 주요 관점은 효율적인 3차원 휠-레일 접촉 해석을 통해 휠-레일 접촉력을 계산하여 철도차량의 동특성 해석의 새로운 방법을 제시하고자 하는 것이다. 이를 통해, 3차원 휠-레일 접촉해석 및 휠셋의 동적 계산식이 제시된다.

• 터널과지하공간
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• 제14권6호
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• pp.423-428
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• 2004

편의상 터널을 평면변형률조건으로 해석하는 경우가 많은데 이때 록볼트는 등가의 연속체로 가정하여 해석한다. 본 연구에서는 3차원해석과2차원 해석을 비교하여 현행의 2차원 해석이 타당한지를 평가하였다. 해석결과 불량한 지반에 대한 2차원 해석에서는 $10\%$ 이상의 변형 오차가 발생하여 3차원적 고려가 필요한 것으로 판단되었다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2001년도 춘계 학술대회논문집
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• pp.1-8
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• 2001

A CFD-based design method for transonic axial compressor blades was developed based on three-dimensional Navier-Stokes flow physics. The method employs a sectional three-dimensional (S3D) analysis concept where the three-dimensional flow analysis is performed on the grid plane of a span station with spanwise flux components held fixed. The S3D analysis produced flow solutions nearly identical to those of three-dimensional analysis, regardless of the initialization of the flow field. The sectional design based on the S3D analysis can include three-dimensional effects of compressor flows and thus overcome the deficiencies associated with the use of quasi-three-dimensional flow physics in conventional sectional design. The S3D design was first used in the inverse triode to find the geometry that produces a specified target pressure distribution. The method was also applied to optimize the adiabatic efficiency of the blade sections of Rotor 37. A new blade was constructed with the optimized sectional geometries at several span stations and its aerodynamic performance was evaluated with three-dimensional analyses.