• 제목/요약/키워드: Solidification

검색결과 1,326건 처리시간 0.029초

실린더 라이너 주조공정에 대한 충전 및 응고해석 (Filling and Solidification Analysis for the Casting Process of Cylinder Liner)

  • 김정훈;김창희
    • 한국주조공학회지
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    • 제24권4호
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    • pp.225-230
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    • 2004
  • Computer simulation of mold filling and solidification has been performed in order to analyze the flow and solidification phenomena for the casting process of cylinder liner. The simulation result of mold filling shows that the molten metal flows into the mold in stable without scattering. The simulation results of solidification indicate that the last solidified area is located in the feeder. The temperature variation in casting is measured in actual casting and the result is compared with calculation result.

EMBR을 이용한 연주공정에서의 난류유동 및 응고에 대한 연구 (A Study on the Turbulent Flow and Solidification in a Continuous Casting Process with Electromagnetic Brake)

  • 김덕수;김우승
    • 대한기계학회논문집B
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    • 제23권3호
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    • pp.374-387
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    • 1999
  • Two-dimensional turbulent fluid flow and solidification were investigated in a continuous casting process of a steel slab with electromagnetic field. The electromagnetic field was described by the Maxwell equations. The enthalpy-porosity relation was employed to suppress the velocity within a mushy region. A revised low-Reynolds number $k-{\varepsilon}$ turbulence model was used to consider the turbulent effects. It is shown that the temperature gradient in the casting direction in the case with EMBR becomes very weak compared to that of the case without EMBR. The results also show that the velocity profiles of the case with solidification are quite different from those of the case without solidification.

암시적 VOF법을 이용한 중력주조에서의 충전 및 응고과정에 대한 연구 (A Study on the Filling and Solidification Process During Gravity Casting Using Implicit VOF Method)

  • 임익태;김우승
    • 대한기계학회논문집B
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    • 제24권1호
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    • pp.102-113
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    • 2000
  • In this study, a three-dimensional gravity casting problem has been examined to investigate a coupled phenomenon of the filling and solidification process. This work simultaneously considers the two key phenomena of metal casting : the fluid flow during mold filling, and solidification process. The VOF method is used to analyze the free surface flow during filling and the equivalent specific heat method is employed to model the latent heat release during solidification. The time-implicit filling algorithm is applied to save the computational time for analyzing the mold filling process. The three-dimensional benchmark problem used in the MCWASP VII has been solved using both the implicit and explicit algorithm, and the present results are compared with the benchmark experimental results and the other numerical results.

보강형 고화제를 이용한 친환경 도로노반조성 방안 (Construction of Environmentally Friendly Roadbed by Reinforecing Type Soil Solidification Agent)

  • 고용국
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.667-671
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    • 2004
  • The purpose of this paper is to study on the construction of environmentally friendly roadbed by reinforcing type soil solidification agent. The soil amendment agent used in this study is friendly to the environment, and has a function of soil-cement-agent solidification. The soil amendment agent was admixed with reinforced fiber material for enhancement of strength and durability of roadbed. The project of trial field test of roadbed construction with special reinforcing soil treatment agent was performed in Gyunggido on December 2003. A series of field and laboratory experiments including unconfined compressive strength, permeability were carried out to investigate the physical and mechanical characteristics of solidified roadbed treated by this reinforced solidifying agent. The results of this research showed that the roadbed using normal and poor soil could be efficiently constructed by treatment of this reinforcing type solidification agent admixed with fiber material.

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반응성 고화제를 이용한 슬러지 고형화 방안 (Solidification of sludge by reactive amendment agent)

  • 고용국
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.869-872
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    • 2004
  • A study on the solidification of sludge by reactive amendment agent was carried out in this paper. The reactive amendment agent used in this study is mainly composed of inorganic solidification agent and reactive adsorptive material. The reactive agent has a function of soil-cement-agent solidification and harmlessness of contaminant in waste. The reactive agent is environmentally friendly material to the surrounding environment. In this study, a series of tests and experiments including unconfined compressive strength, permeability, pH test, constituent analysis, leaching test were carried out to analyse engineering and environmental characteristics of solidified sludge treated reactive agent. The result of this research shows that the solidified sludge treated reactive agent is increased in strength and decreased in contaminant concentration.

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이성분혼합물의 응고과정중 이중확산대류의 가시화 (Visualization of double-diffusive convection during solidification processes of a binary mixture)

  • 정우호;정재동;유호선;이준식
    • 대한기계학회논문집B
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    • 제22권4호
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    • pp.440-451
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    • 1998
  • An experimental study has been conducted to investigate solidification of NH$_{4}$CI-H$_{2}$0 mixtures inside a vertical rectangular enclosure. Solidification process is visualized by the shadowgraph method. Emphasis is placed on the effect of solidification parameters such as the aspect ratio, cooling wall temperature and initial composition. The aspect ratio shows a dominant effect on the number and developing time of the double diffusive layers which reveals the relative strength of solutal convection to thermal convection. Similar flow pattern is observed when the concentration difference between interdendritic liquid and the pure liquid which drives solutal convection is the same regardless of the different cooling wall temperature and initial concentration.

싱크로트론 X-선 투과영상법을 활용한 응고거동 실시간 관찰 (Real Time Imaging of Solidification Behavior by Synchrotron X-ray Radiography)

  • 이상목;안전수행
    • 한국주조공학회지
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    • 제30권1호
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    • pp.5-13
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    • 2010
  • This article aims to introduce the synchrotron radiation for its utilization in the casting and solidification fields as an unique tool for observation of real time phenomena of molten metal during solidification. General features of the synchrotron radiation were briefly introduced for readers in the casting and solidification fields, with no background regarding to synchrotron radiation. And basic principles of imaging technologies using synchrotron light for in-situ observation of molten metal were explained together with exemplary research works, which were reported on the casting and solidification fields in recent years. As a practical guide, real time observation of Al-Si casting alloy was introduced with experimental facilities, image acquisition, and processing together with representative results.

산업부산물을 이용한 비소성 시멘트의 중금속 고정화 (Solidification of Heavy metals of Non-Sintering Cement using Industrial By- Products)

  • 안양진;윤성진;문경주;소양섭
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.763-768
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    • 2003
  • This study is to specify the properties of solidification/stabilization of heavy metals in connection with looking over the hydration features of non-sintering cement using industrial by-products. In this study, we added Cr and Pb to non-sintering cement(NSC), ordinary portland cement (OPC), and Blast-furnace slag cement(BSC) to specify the solidification process. Heavy metal leaching test was carried out to evaluate solidification degree of various cement. Follow result, marking no higher than 0.7% of un-solidified ratio of BSC was the most predominant result when we mixed the materials with Cr. 5.8% for NSCI and 6.2% for NSC2. On the contrary, in case of adding Pb, NSCl and NSC2 made better solidification results than those of OPC(below 0.2%) and BSC(below 0.05%), marking nearly 0%.

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스테인리스강의 용접 특성에 미치는 합금원소의 영향 (The effection of alloying elements on welding characteristics of stainless steel)

  • 정호신;배동수;엄동석
    • 한국해양공학회지
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    • 제11권1호
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    • pp.16-23
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    • 1997
  • Stainless steel are widely applicable in various engineering fields for its exellent corrosion and impact ressistance. Austenitic weld metal has some ferrite for preventing solidification cracking by ASME specification. Several family of austenic stainless steel contains varying ferrite contents. But ferrite in austenic stainless steels is adversely affect weld metal toughness and since fully austenic grades are known to have good toughness. Austenic stainless steel has various alloying addition for improving corrosion resistance, impact toughness and solidification crack resistance. The effect of various alloying elements are not found to be clear in present. From this view of point, this study tried to establish the criteria of alloy design for austenic stainless steel by controlling primary solidification mode and clarifying the effect of several alloying elements.

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융액 일방향 응고법에 의한 ${\gamma}$-$6Bi_2O_3$.$GeO_2$ 투명 다결정체의 제조 (Preparation of Transparent ${\gamma}$-$6Bi_2O_3$.$GeO_2$ Polycrystals by Unidirection Solidification of Melt)

  • 김호건;김명섭;류일환
    • 한국세라믹학회지
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    • 제27권4호
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    • pp.567-573
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    • 1990
  • Solidification condition for preparing transparent ${\gamma}$-6Bi2O3.GeO2 polycrystals by unidirectional solidification of melt, were investigaetd and the properties of the polycrystals prepared were measured. The ${\gamma}$-6Bi2O3.GeO2 polycrystals showing transparency like a single crystal were obtained by the unidirectional solidification of ${\gamma}$-6Bi2O3.GeO2 melt at a solidification rate of 0.5mm/h under a thermal gradient of 12$0^{\circ}C$/cm. The transparent polycrystals obtained showed the same photoconduction and optical activity as the ${\gamma}$-6Bi2O3.GeO2 single crystals grown by Czochralski method. But the electro-optic effect of polycrystals was heterogeneous because the colummar ${\gamma}$-6Bi2O3.GeO2 crystals were not oriented to the particular crystallographic direction.

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