• 제목/요약/키워드: foam

검색결과 2,434건 처리시간 0.03초

구조용 폼과 플라스틱 보강재를 적용한 모자 단면 부재의 좌굴 특성 분석 (Analysis of Buckling Characteristics for Hat Section Member Using Structural Foam and Plastic Reinforcement)

  • 이태현;신성기
    • 한국자동차공학회논문집
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    • 제16권2호
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    • pp.114-119
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    • 2008
  • The modern automotive industry develops innovative vehicle designs to meet increasing stability of car and performance demands of their customers. The improvement of frame rigidity by the structural foam is thought to be an effective means to improve the performance because of high applicability and minimum weight. The object of this paper is to examine the use of structural foam in a hat section as an optimum reinforcing means, to compare the reinforcing performance of structural foam versus a plastic reinforcement. The result of this paper indicated that reinforcing efficiencies are achieved by structural foam and plastic reinforcement shape.

Improving buckling response of the square steel tube by using steel foam

  • Moradi, Mohammadreza;Arwade, Sanjay R.
    • Structural Engineering and Mechanics
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    • 제51권6호
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    • pp.1017-1036
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    • 2014
  • Steel tubes have an efficient shape with large second moment of inertia relative to their light weight. One of the main problems of these members is their low buckling resistance caused from having thin walls. In this study, steel foams with high strength over weight ratio is used to fill the steel tube to beneficially modify the response of steel tubes. The linear eigenvalue and plastic collapse FE analysis is done on steel foam filled tube under pure compression and three point bending simulation. It is shown that steel foam improves the maximum strength and the ability of energy absorption of the steel tubes significantly. Different configurations with different volume of steel foam and composite behavior is investigated. It is demonstrated that there are some optimum configurations with more efficient behavior. If composite action between steel foam and steel increases, the strength of the element will improve, in a way that, the failure mode change from local buckling to yielding.

디젤 엔진에서 금속 폼을 적용한 SCR 촉매의 특성 분석 (Characteristic Analysis of a SCR System using a Metal Foam in Diesel Engines)

  • 김용래;최교남
    • 한국분무공학회지
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    • 제18권4호
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    • pp.196-201
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    • 2013
  • SCR(Selective Catalytic Reduction) is a major after-treatment solution to reduce NOx emission in recent diesel engines. In this study, a metal foam is applied as an alternative SCR substrate and tested in a commercial diesel engine to compared with a conventional ceramic SCR system. Basic engine test from ND-13 mode shows that a metal foam catalyst has lower NOx conversion efficiency than a ceramic catalyst especially over $350^{\circ}C$. A metal foam catalyst has characteristics of high exhaust gas pressure before a SCR catalyst and high heat transfer rate due to its material and structure. NOx conversion efficiency of a metal foam catalyst shows an increasing tendency along with the increase of exhaust gas temperature by $500^{\circ}C$. The effect of urea injection quantity variation is also remarkable only at high exhaust gas temperature.

단열재의 무게변화와 열전도도와의 상관관계에 관한 실험적 연구 (Experimental Study of the Relationship between Weight Variation and Thermal Conductivity in Polyurethane Foam)

  • 이효진
    • 설비공학논문집
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    • 제27권5호
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    • pp.241-246
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    • 2015
  • Cellular foamed insulation such as polyurethane foam ages and degrades the thermal conductivity. Aging of foam is a result from the diffusion of gases, initially consisting of $CO_2$ but eventually replaced by air from the environment. The variation of the cell gas content with time is primarily influenced by the increase of thermal conductivity of the cellular foam. The weight of foam also changes as the gas diffuses and exchanges. In this study, a weight measurement method has been proposed to evaluate the effective diffusion coefficients of $CO_2$ and Air, $D_{CO2}=7.08504E-11$ and $D_{air}=4.86086E-12$, respectively and are compared with the gas analysis method.

방재기술 - 수성막 형성 FOAM (AFFF)

  • 한국화재보험협회
    • 방재와보험
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    • 통권36호
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    • pp.31-33
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    • 1988
  • 1960년대까지는 저팽창단백포가 유류화재의 진압에 주로 사용되었으니 불소화합물 계면활성제로부터 유출된 합성 AFFF를 개발하면서 해수로도 이의 사용이 가능하고 지역 및 유출화재 예방에서 AFFF 특유의 초기진압효과 및 대형화재를 방지한다는 장점 때문에 널리 사용되고 있으며, 석유화학산업의 저장탱크지역 및 공정지역에서 AFFF와 FPF가 주로 사용되며 부두시설(Oilrig, Marine Tanker, 해상 / 해변터미널)에는 AFFF의 사용이 지배적이다. 현재 사용되고 있는 foam으로는 단백포(Protein: PF), 불화단백포(Fluoroprotein: FPF), 막형성 불화단백포(Film Forming Fluoroprotein Foam: FFFP), 고팽창폼(High Expansion Foam), 수성막 형성폼(Aqueous Film Foaming Foam: AFFF), 알콜폼(Alcohol Resistant Foam: ATD) 등이 있으니 본고에서는 AFFF 중심으로 소개한다.

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Development of a numerical simulation tool for efficient and robust prediction of ship resistance

  • Kim, Geon-Hong;Park, Sanghoon
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제9권5호
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    • pp.537-551
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    • 2017
  • In this paper, a two-phase flow solver $HiFoam^{(R)}$ has been developed based on the $OpenFOAM^{(R)}$ to predict resistance of a ship in calm water. The VOF method of $OpenFOAM^{(R)}$ was reviewed and a simple flux limiter was introduced to enhance the robustness of the solver. The procedure for predicting ship motion was modified by introducing Quasi-Steady Fluid-Body Interaction (QS-FBI) with least square regression to improve the efficiency. Other minor factors were considered as well in terms of the efficiency and robustness. The HiFoam was applied to KCS and JBC simulations to validate its efficiency and accuracy by comparing the results to experimental data and STAR-CCM+. The $HiFoam^{(R)}$ was also applied to various ships and it showed good agreements to the experimental data.

Effect of Invertase on the Batch Foam Fvactionation of Bromelain

  • D. Micheal Ackermann;Jr., Matthew L. Stedman;Samuel Ko;Ales Prokop;Park, Don-Hee;Robert D. Tanner
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제8권3호
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    • pp.167-172
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    • 2003
  • Foam fractionation can be used to enrich a hydrophobic protein such as bromelain from an aerated dilute protein solution because the protein foams. On the other hand, a protein such as invertase, which is hydrophilic, is not likely to foam under similar aerated conditions. While a foam fractionation process may not be appropriate for recovering a hydrophilic protein alone, it is of interest to see how that non-foaming protein affects the foaming protein when the two are together in a mixture. The bromelain enrichment, activity and mass recovery were observed as a function of the solution pH in order to explore how invertase can affect the recovery of bromelain in a foam fractionation process.

알루미늄 폼으로 충진된 스테인레스 관의 3 점 굽힘 특성에 관한 수치적 연구 (A Numerical Study on The Three Point Bending Behavior of Aluminum Foam Filled Stainless Steel Tube)

  • 하산;김엄기;전성식;이창훈;이효진;조성석
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.388-393
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    • 2004
  • A comprehensive numerical study on the three point bending behavior of Aluminum foam-filled stainless steel tube has been performed. Aluminium alloy foams with various densities were produced and their mechanical properites were evaluated. Finite element(FE) analysis of three point bending test was performed to evaluate bending behavior of foam filled cylindrical structures. Results showed that foam filling offered remarkable increase of bending resistance and enhanced the crashworthiness of the structure. It turned out to prevent the inward fold formation at the compression flange, resulted into the multiple propagating folds and increased the load carrying capacity.

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Experimental study on the fatigue performance of aluminum foam sandwich with 304 stainless steel face-sheet

  • Yan, Chang;Jing, Chuanhe;Song, Xuding
    • Steel and Composite Structures
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    • 제39권3호
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    • pp.229-241
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    • 2021
  • This work focused on aluminum foam sandwich (AFS) with different foam core densities and different face-sheet thicknesses subjected to constant amplitude three-point bending cyclic loading to study its fatigue performance. The experiments were conducted out by a high frequency fatigue test machine named GPS-100. The experimental results showed that the fatigue life of AFS decreased with the increasing loading level and the structure was sensitive to cyclic loading, especially when the loading level was under 20%. S-N curves of nine groups of AFS specimens were obtained and the fatigue life of AFS followed three-parameter lognormal distribution well. AFS under low cyclic loading showed pronounced cyclic hardening and the static strength after fatigue test increased. For the same loading level, effects of foam core density and face-sheet thickness on the fatigue life of AFS structure were trade-off and for the same loading value, the fatigue life of AFS increased with aluminum foam core density or face-sheet thickness monotonously. Core shear was the main failure mode in the present study.

ALC 대체를 위한 선발포 경량기포콘크리트의 최적배합 선정 연구 (Study on the Optimal Mix Proportions of Lightweight Foam Concrete for Substitution of ALC )

  • 최선미;김범수;김진만
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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    • pp.199-200
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    • 2023
  • This paper presents a study on the selection of optimal mix proportions for producing lightweight pre-foam concrete as a substitute for Autoclaved Lightweight Concrete (ALC) without the accelerated curing. The study was conducted using a rapid hardening binder made from by-products of the steel industry as the primary raw material. The experimental results established the optimal mix proportions, which included retarder content, water/binder ratio, foam content, and fiber inclusion amount, for the production of lightweight foam concrete. The optimal mix proportion was determined to have a retarder content at the minimum amount required to secure the working time, W/B of 35%, a foam content limited to 65% or less, and a fiber inclusion amount of 0.05% or less.

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