• Journal of Magnetics
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• 제20권4호
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• pp.444-449
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• 2015

Soft magnetic composites (SMCs) are especially suitable for the construction of low-cost, high-performance motors with 3-D magnetic fields. The main advantages of SMCs is that the iron particles are insulated by the surface coating and adhesive used for composite bonding, the eddy-current loss is much lower than that in laminated steels, especially at higher frequencies, and the hysteresis loss becomes the dominant component of core losses. These properties enable machines to operate at higher frequencies, resulting in reduced machine size and weight. In this paper, 3-D topologies are proposed that enable the application of SMCs to effectively reduce losses in high-speed permanent magnet (PM) motors. In addition, the electromagnetic field characteristics of the motor topologies are evaluated and compared using a non-linear finite element method (FEM) based on 3-D numerical analysis, and the feasibility of the motor designs is validated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.365-368
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• 2006

RBSN Method, Rigid-Body-Spring Network Method, is a structural analysis method that overcomes the problems faced in FEM analysis of concrete or crack forming structures. In RBSN, irregular lattices are used to model structural components consisting of bulk material, curvilinear reinforcements, and their interfaces. Because reinforcements and their interfaces in the bulk material are freely positioned, meshing is irrespective of the geometry of the representing bulk material. In this paper, RBSN method of 3D is applied in simulating the pull-out test of FRP (Fiber Reinforced Polymer) embedded in concrete. The comparison of analysis results to experimental results shows that RBSN method simulates the shear-slip behavior very precisely. From the analysis results, 3D RBSN method is proven to be an effective and accurate analysis method for concrete structural analysis. Also, the results show that RBSN method can be a potential analysis method for concrete structures that can replace the current FEM analysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.235-237
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• 1999

This paper has proposed a method to estimate effective length of a 30 KVA super-conducting generator using 3-dimensional FEM program. Flux linkage of the stator coil is calculated by the FEM program and the induced voltage is computed using the simple Faraday's law.

• 한국가스학회지
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• 제10권2호
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• pp.40-46
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• 2006

본 논문은 다구찌 실험 설계법을 이용하여 O-링을 장착하는데 필요한 사각 그루브의 최적설계를 위해 FEM으로 최대코시응력과 최대변형률에 대하여 해석하였다. 다구찌 설계방법은 LPG 충전노즐의 내경측에 밀봉을 위해 설치하는 O-링 그루브의 설계변수를 최적화 하는데 대단히 유용하다. FEM과 함께 다구찌 설계기법을 적용하여 계산된 해석결과에 따르면, 최적화 설계치수를 단지 9번의 반복 실험법에 의해 설계변수의 치수를 최적의 조건으로 얻을 수 있다는 측면에서 간편한 최적설계 기술이다. 이것은 다구찌 설계 실험법이 사각형상의 O-링 그루브를 설계하는 간단한 방법으로 대단히 유용하다는 것이다. 다구찌 설계기법에 기초한 해석결과에 의하면, O-링 그루브의 기하학적 형상에 대한 최적치수는 h=2.5mm, d=2.74 mm, c=0.15 mm, w=3.0 mm으로 각각 요약될 수 있다. 본 연구는 공급된 LPG 가스압력이 18 $kg/cm^2$인 상태에서 밀봉성과 안전성을 고려하면 초기압축률은 8.7%로 유지하는 것이 가장 효과적이라는 사실을 제공한다.

• 한국도로학회:학술대회논문집
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• 한국도로학회 2008년도 추계학술대회 논문집
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• pp.217-220
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• 2008

• 대한의용생체공학회:의공학회지
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• 제20권5호
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• pp.581-586
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• 1999

척추의 생체역학적 해석을 위한 유한요소기법을 이용한 컴퓨터 시뮬레이션은 척추의 손상에 대한 발생원인과 기전을 이해하고 치료의 효과를 예측하는 유용한 수단으로 기대되고 있다. 본 논문에서는 요추의 2차원 CT 영상을 이용하여 유한요소해석을 위한 척추의 3차원 모델링에 소비되는 많은 시간을 줄일 수 있도록 3차원 형상모델을 CT 형상 데이터와 형상변수를 이용, 각각 구현하는 과정을 자동화하여 이를 비교하였다.

• 한국산학기술학회논문지
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• 제15권11호
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• pp.6458-6463
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• 2014

본 논문의 목적은 38인승 승강기 제동장치의 설계 및 유한요소해석이다. 최근 승강기의 안전성이 부각되면서 비상 제동장치의 필요성이 높아졌으며 이에 따라 새로 개발된 제동장치의 안전성을 확인하기 위하여 Solid Works를 활용하여 모델링 하였으며 유한요소해석 코드인 ANSYS를 활용하여 유한요소해석을 수행하였다. 해석결과로서 총변형량, 응력, 변형률을 구하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1565-1568
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• 2003

The backward extrusion process is one of the commonly used metal forming processes. In this paper. a battery case which has the rectangular section, is analyzed using a 3D metal forming package(MSC.Superforge). This pacakge uses the finite volume analysis method. It is shown that the MSC.Superforge package using finite volume method provides result very close to those obtained from a finite element analysis package(MSC.Superform). However, the simulation time using the finite volume method was almost 10 % of the simulation time consumed by the other package using finite element method. Moreover, the finite volume method used in MSC.Superforge can eliminate the remeshing problems that make the simulating a metal forming process with severe deformation, such as the extrusion process, so difficult.

• 한국기계가공학회지
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• 제11권4호
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• pp.39-45
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• 2012

In this paper, process conditions are investigated for elimination of the grain coarsening and improved material flow during forging process by both of experiments and FEM analysis. Particular interest has been given to understand role of preform shape on the grain coarsening behavior and magnitude of the hammer forging load. As the results of FEM simulation by using DEFORM-3D, the simulated forging loads were 2,200ton in the case of a machined bar which is machined from 65mm to 60mm diameter, and below 1,900ton in the case of machined preform, respectively. The use of preform has been beneficial for reduction of the forging load and elimination of the grain coarsening. However, in the case of as received bar and the round bar, which was machined to 2.5mm thickness in surface layer, some degree of local grain coarsening behavior has been observed. The optimized preform shape could be properly designed by applying the FEM simulation.

• Geomechanics and Engineering
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• 제9권4호
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• pp.415-426
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• 2015

Researches have been done to discover ways to strengthen peat soil deposits. In this model study, fibrous peat that is the most compressible types of peat has been reinforced with precast peat columns stabilized with ordinary Portland cement and polypropylene fibres. Rowe cell consolidation tests as well as plate load tests (PLTs) were conducted on various types of test samples to evaluate the strength and deformation of untreated peat and peat reinforced by various types of columns. PLTs were conducted in a specially designed and fabricated circular steel test tank. The compression index ($C_c$) and recompression index ($C_r$) of fibrous peat samples reduced considerably upon use of precast columns. Also, PLT results confirmed the results obtained from Rowe cell tests. Use of polypropylene fibres added to cement further decreased ($C_c$) and ($C_r$) and increased load bearing capacity of untreated peat. Finite element method (FEM) using Plaxis 3D was carried out to evaluate the stress distributions along various types of tested samples and also, to compare the deformations obtained from FEM analysis with the actual maximum deformations found from PLTs. FEM results indicate that most of the induced stresses are taken on the upper portion of tested samples and reach their maximum values below the loading plate. Also, a close agreement was found between actual deformation values obtained from PLTs and values resulted from FEM analysis for various types of tested samples.