• 제목/요약/키워드: Material Mixing Method

검색결과 387건 처리시간 0.027초

다중재료 구조물의 위상 최적화를 위한 재료혼합법의 개발 (Development of a Material Mixing Method for Topology Optimization of Multiple Material Structures)

  • 한석영;이수경
    • 대한기계학회논문집A
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    • 제28권6호
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    • pp.726-731
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    • 2004
  • This paper suggests a material mixing method to mix several materials in a structure. This method is based on ESO(Evolutionary Structural Optimization), which has been used to optimize topology of only one material structure. In this study, two criterions for material transformation and element removal are implemented for mixing several materials in a structure. Optimal topology for a multiple material structure can be obtained through repetitive application of the two criterions at each iteration. Two practical design examples of a short cantilever are presented to illustrate validity of the suggested material mixing method. It is found that the suggested method works very well and a multiple material structure has more stiffness than one material structure has under the same mass.

진화적 구조 최적화를 이용한 재료 혼합법의 개발 (Development of a Material Mixing Method using ESO)

  • 한석영;이수경;신민석
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2003년도 추계학술대회
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    • pp.259-264
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    • 2003
  • This paper suggests a material mixing method to mix several materials in a structure. This method is based on ESO(Evolutionary Structural Optimization), which has been used to optimize topology of only one material structure. In this study, two criterions for material transformation and element removal are implemented for mixing several materials in a structure. Optimal topology for a multiple material structure can be obtained through repetitive application of the two criterions at each iteration. Two practical design examples of a short cantilever are presented to illustrate validity of the suggested material mixing method. It is found that the suggested method works very well and a multiple material structure has more stiffness than one material structure has under the same mass.

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PCB판의 위상 최적화를 위한 재료혼합법의 개발 (Development of a Material Mixing Method for Topology Optimization of PCB Substrate)

  • 한석영;김민수;황준성;박재용;최상혁;이병주
    • 한국공작기계학회논문집
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    • 제16권1호
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    • pp.47-52
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    • 2007
  • A material mixing method to obtain an optimal topology for a structure in a thermal environment was suggested. This method is based on Evolutionary Structural Optimization(ESO). The proposed material mixing method extends the ESO method to a mixing several materials for a structure in the multicriteria optimization of thermal flux and thermal stress. To do this, the multiobjective optimization technique was implemented. The overall efficiency of material usage was measured in terms of the combination of thermal stress levels and heat flux densities by using a combination strategy with weighting factors. Also, a smoothing scheme was implemented to suppress the checkerboard pattern in the procedure of topology optimization. It is concluded that ESO method with a smoothing scheme is effectively applied to topology optimization. Optimal topologies having multiple thermal criteria for a printed circuit board(PCB) substrate were presented to illustrate validity of the suggested material mixing method. It was found that the suggested method works very well for the multicriteria topology optimization.

마이크로 채널 내의 혼합효과 정량화를 위한 물질신장 사상법 (Method of Material-Stretching Mapping for Quantification of Mixing Effect in Microchannels)

  • 서용권
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2005년도 춘계 학술대회논문집
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    • pp.1-13
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    • 2005
  • Fluid flows within microchannels are characterized by low Reynolds numbers. Therefore the effect of mixing is a crucial factor in design of the channels. Since the action of the electro-osmotic or magnetic forces used in the mixing enhancement is usually periodic in the three-dimensional channel configuration, use of the various concepts of chaotic advection is reasonable in the quantification of the stirring effect. In this paper, the details of the method of material-stretching mapping is explained. The actual application of the method to the screw extruder is also presented.

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격자 볼츠만법을 이용한 리튬이온전지의 활물질 혼합비에 대한 함침성의 영향 (Effect of Mixing Ratio of Active Material on the Wettability in Lithium-Ion Battery Using Lattice Boltzmann Method)

  • 전동협
    • 대한기계학회논문집B
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    • 제40권1호
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    • pp.47-53
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    • 2016
  • 격자 볼츠만법을 이용하여 리튬이온전지의 전극 내 발생하는 전해액 함침 현상에 관하여 연구하였다. 최근 리튬이온전지는 용량 증가 및 에너지밀도 향상을 위하여 전극 설계시 활물질에 미세입자를 혼합하고 있어, 이로 인하여 전해액 함침성에 영향을 미치게 될 수 있다. 본 연구에서는 활물질 혼합율에 따른 전해액 분포와 포화도 변화를 알아보았다. 활물질 혼합비의 변화는 전극 내 전해액 함침 메커니즘에 영향을 주어, 전해액 함침속도와 함침도가 변화함을 확인하였다.

In-situ 용탕혼합 합성법에 의한 Al-TiB2 복합재료의 LES 기법 모델링 및 제조 (LES Method Modeling and Fabrication of Al-TiB2 Composite by In-situ Melt Mixing Process)

  • 박정수;김종훈;하만영;박봉규;박영호;박익민
    • 대한금속재료학회지
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    • 제46권6호
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    • pp.382-389
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    • 2008
  • To manufacture Al MMCs, in-situ melt mixing process is used because it is free from contamination, and it makes reinforcements homogeneously dispersed. Large eddy simulation method is used to find the optimum melt mixing condition. At the Re 3000, the most suitable mixing is occurred between Al-Ti and Al- B melts. The in-situ formed $TiB_2$ particles has the size varying from 40 nm to 130 nm, due to the increase of cooling rate, and exhibits a homogeneous dispersion. And the interface between reinforcement and matrix is clean. Both hardness and Young's modulus of this composite are improved with increasing the cooling rate.

알지네이트 인상재의 혼합방법과 트레이 어드헤시브 도포에 따른 모형의 정확도 비교 (COMPARISON OF THE ACCURACY OF STONE CASTS MADE FROM ALGINATE IMPRESSION MATERIAL BY MIXING METHODS AND APPLICATION OF TRAY ADHESIVE)

  • 김진형;정문규
    • 대한치과보철학회지
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    • 제39권5호
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    • pp.492-501
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    • 2001
  • The use of alginate impression materials today is prevalent because of its efficiency and simplicity in clinical settings. Unfortunately, the simplicity of the procedure tends to lull the dentist into a sense of well-being, and lead him into using careless or sloppy technique. Alginate impression materials are used to fabricate diagnostic and preliminary casts, and the final cast. Incorrect use of this material is known to affect the accuracy of the final prosthesis. The purpose of this study was to compare the effect of different mixing methods of alginate impression material and tray adhesive on the accuracy of the stone cast produced by each method. A total of 30 stone casts were produced by using 3 different types of mixing methods (10 stone cast for each mixing method, respectively). The first method utilized an automatic-mixing machine to mix alginate while the second method was carried out manually, strictly following manufacturer's instructions. The third method also involved manual mixing, but did not follow the manufacturer's instructions and was done in a random fashion. Also, 20 additional stone casts were produced by using alginate with or without tray adhesives were included in the study to evaluate effects of tray adhesives on the accuracy of alginate impression. 10 stone casts were produced by adding tray adhesives to the interior surface of the impression tray prior to taking the impression. The other 10 excluded this step. A total of 50 stone casts were analyzed by the three-dimensional measuring machine to measure and compare the dimensional changes of the impression material of each group. The results are as follows. 1. No significant difference was found between the automatic mixing group and the manually-mixing group(p>0.05). 2. For the group that followed manufacturer's instructions, less dimensional changes were record ed than the group that didn't in measuring distanced 4(p<0.05). 3. The group that used tray adhesives showed less dimensional changes(p<0.05). The findings revealed that mechanical methods of mixing alginate impression materials had little influence on dimensional changes. However, it is proven that following manufacturers instructions in alginate impression taking is an important step in acquiring accurate impressions and tray adhesives may play an important role in enhancing the results.

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물질신장 사상법에 의한 혼합효과의 정량화 (Quantification of the Mixing Effect by Using the Method of Material-Stretching Mapping)

  • 서용권
    • 한국전산유체공학회지
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    • 제9권4호
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    • pp.20-33
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    • 2004
  • In this study a stretching-mapping method is proposed for calculating the materials' stretching exponents, which are to be used in quantification of the mixing effect. In this method, the mapping tensor associated with the deformation of each fluid material is first obtained. Then deformations of a lot of materials are obtained by applying the mapping tensor. The local stretching rates and their space-average values are next computed with the mapped deformations. Application to a simple time-periodic flow within a cavity shows that the method is indeed effective compared with the conventional method; i.e. the mapping method is fast and yields the same results as the conventional one.

난류 용탕 In-situ 합성 믹서의 설계 및 Cu-TiB2 나노 복합재료의 제조 (Design of Turbulent In-situ Mixing Mixer and Fabrication of Cu-TiB2 Nanocomposities)

  • 최백부;박정수;윤지훈;하만영;박용호;박익민
    • 한국재료학회지
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    • 제17권1호
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    • pp.11-17
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    • 2007
  • Turbulent in-situ mixing process is a new material process technology to get dispersed phase in nanometer size by controlling reaction of liquid/solid, liquid/gas, flow ana solidification speed simultaneously. In this study, mixing which is the key technology to this synthesis method was studied by computational fluid dynamics. For the simulation of mixing of liquid metal, static mixers investigated. Two inlets for different liquid metal meet ana merge like 'Y' shape tube having various shapes and radios of curve. The performance of mixer was evaluated with quantitative analysis with coefficient of variance of mass fraction. Also, detailed plots of intersection were presented to understand effect of mixer shape on mixing. The simulations show that the Reynolds number (Re) is the important factor to mixing and dispersion of $TiB_2$ particles. Mixer was designed according to the simulation, and $Cu-TiB_2$ nano composites were evaluated. $TiB_2$ nano particles were uniformly dispersed when Re was 1000, and cluster formation and reduction in volume fraction of $TiB_2$ were found at higher Re.

용액혼합법에 따른 나노복합재료 분산성 및 전기적 특성 (Dispersibility, Electrical Property of Nano-Composite by Solution Mixing Method)

  • 양훈;박대희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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    • pp.73-74
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    • 2008
  • In this paper, we have investigated dispersibility, volume resistivity of nano-composite by solution mixing method. Dispersibility measured by FE-SEM(Field Emission Scanning Electron Microscope. And volume resistivity measured by ASTM D991. To expect interaction used dual filler system. But, dual filler system had influence on polymer complex. So, polymer chain mobility doesn't resist.

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