• 제목/요약/키워드: Liquid structure

검색결과 1,708건 처리시간 0.028초

연소시 발생하는 파면의 나노 사이즈 두께 측정: 수치적 접근 (Measuring Nano-Width of Wave Fronts in Combustion: a Numerical Approach)

  • 여재익
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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    • pp.20-27
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    • 2005
  • I consider the structure of steady wave system which is admitted by the continuum equations for materials that undergo phase transformations with exothermic chemical reaction. In particular, the dynamic phase front structures between liquid and gas phases, and solid and liquid phases are computationally investigated. Based on the one-dimensional continuum shock structure analysis, the present approach can estimate the nano-width of waves that are present in combustion. For illustration purpose, n-heptane is used in the evaporation and condensation analysis and HMX is used in the melting and freezing analysis of energetic materials of interest. On-going effort includes extension of this idea to include broad range of liquid and solid fuels, such as rocket propellants.

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유체 슬로싱모드가 탱크의 진동에 미치는 영향에 대한 연구 (A Study on Vibration Characteristics with Sloshing Mode Effect in Water Tank Structure)

  • 배성용
    • 대한조선학회논문집
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    • 제40권6호
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    • pp.88-95
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    • 2003
  • Liquid storage rectangular tank structures are used in many fields of airplane and marine engineering. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance. Therefore it is essentially important to estimate vibration characteristics of tank structures. Many Investigators studied the vibration of cylindrical and rectangular tank structures containing still fluid. In general, the eigenbehavior of interior liquid is characterized by the sloshing mode while that of the structure by the bulging mode. However, the structure deformation to the sloshing mode and the liquid free-surface fluctuation to the bulging mode have been neglected in the classical added-mass computation. in the present paper, we study the vibration characteristics with sloshing mode effect.

Fusion Mechanism of Liquid according to the Significant Liquid Structure Theory

  • Kim, Ui-Rak;Jhon, Mu-Shik
    • Nuclear Engineering and Technology
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    • 제3권1호
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    • pp.33-36
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    • 1971
  • 액체에 대한 Significant Structure 이론을 토대로 하여 융해의 기본적 원리를 성공적으로 논의하였다. 융해의 이론을 실증하는 보기로서 융점에서의 부지의 팽창을 용융염등 몇가지 액체에 대해 계산하였다. 계산결과는 실험치와 이론치 사이에 좋은 일치를 보여주고 있다. 용융염의 연구는 원 자료에 쓰는 고온도 액체의 성질과 구조를 이해하는데 도움을 줄 것이 다.

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액체암모니아 처리 면직물의 물성 및 염색성 (Physical Properties and Dyeability of Cotton Fabrics Treated with Liquid Ammonia)

  • 전성기;이창수;임용진;이청;김태경;이혜정
    • 한국염색가공학회지
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    • 제15권4호
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    • pp.73-79
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    • 2003
  • It is generally known that cotton treated with liquid ammonia has better soft handle, wrinkle recoveries and stability of appearance as compared with the alkali mercerized cotton. In this study, the various cotton fabrics treated with liquid ammonia$(NH_3)$, sodium hydroxide(NaOH) and sodium hydroxide(NaOH)/liquid ammonia$(NH_3)$ and untreated cotton fabric were investigated and compared in terms of physical properties and dyeing behavior. As the result, the strength of four kinds of cotton fabrics were similar. But the elongation of cotton treated with liquid ammonia increased slightly. Liquid ammonia treatment reduced the crystallinity of cotton and the crystalline structure of cotton transformed from cellulose 1 to mixed structure of celluloseIand III. In dyeing, dyeing rate decreased but equilibrium dye uptake increased by liquid ammonia treatment of cotton fabrics.

Experimental study on tuned liquid damper performance in reducing the seismic response of structures including soil-structure interaction effect

  • Lou, Menglin;Zong, Gang;Niu, Weixin;Chen, Genda;Cheng, Franklin Y.
    • Structural Engineering and Mechanics
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    • 제24권3호
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    • pp.275-290
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    • 2006
  • In this paper, the performance of a tuned liquid damper (TLD) in suppressing the seismic response of buildings is investigated with shake table testing of a four-story steel frame model that rests on pile foundation. The model tests were performed in three phases with the steel frame structure alone, the soil and pile foundation system, and the soil-foundation-structure system, respectively. The test results from different phases were compared to study the effect of soil-structure interaction on the efficiency of a TLD in reducing the peak response of the structure. The influence of a TLD on the dynamic response of the pile foundation was investigated as well. Three types of earthquake excitations were considered with different frequency characteristics. Test results indicated that TLD can suppress the peak response of the structure up to 20% regardless of the presence of soils. TLD is also effective in reducing the dynamic responses of pile foundation.

면진된 유체저장탱크의 비선형 유체-구조물 상호작용 해석 (Analysis of Fluid-Structure Interactions Considering Nonlinear Free Surface Condition for Base-isolated Fluid Storage Tank)

  • 김문겸;임윤묵;조경환;정승원;어준
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 추계 학술발표회논문집
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    • pp.481-488
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    • 2003
  • A fluid-structure-isolator interaction program was developed in this study. The behavior of liquid regions are simulated by the boundary element method, and then the technique of analyzing the free surface motion in time domain is developed by using the nonlinear free surface boundary condition(NFBC) and the condition of interface between the structure and the fluid. Structure regions are modeled by the finite element method. In order to construct the governing equation of the fluid structure interaction(FSI)problem in time domain, the finite elements for a structure and boundary elements for liquid are coupled using the equilibrium condition, the compatibility condition and NFBC. The isolator is simulated by equation proposedin 3D Basis Me. In order to verify the validity and the applicability of the developed fluid- structure -Isolator interaction program, The horizontal forced vibration analysis was performed. The applicability of the developed method is verified through the artificial seismic analysis of real size liquid storage tank.

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액체구조에 관한 천이상태이론의 싸이클로 핵산에 대한 적용 (Transient State Theory of Significant Liquid Structure applied to Cyclohexane)

  • 이해방;장세헌
    • 대한화학회지
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    • 제10권3호
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    • pp.129-132
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    • 1966
  • 싸이클로핵산의 분자는 액체상태에서 대부분이 chair form으로 되어 있음이 알려져 있다. 이 사실로 부터 싸이클로핵산의 액체는 Chair form 만으로 되어있다는 가정하에 액체구조의 천이상태이론을 적용시켜 상태함을 구하고 이로부터 싸이클로핵산의 몰부피, 증기압, 한계점, 증발엔트로피 및 압축률 등의 열역학적 량을 계산한 결과 측정치와 잘 맞는 값을 얻었다.

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Effect of Liquid Surface Treatments on Field Emission Properties of Carbon Nanotube Cathodes

  • Lee, Ji-Eon;An, Young-Je;Shin, Heon-Cheol;Chung, Won-Sub;Cho, Young-Rae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.486-489
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    • 2007
  • Carbon nanotube (CNT) cathodes having a trench structure similar to the structure of the gated triodetype cathode were successfully fabricated by a screenprinting method with multi-walled carbon nanotubes. We observed that a liquid method not only readily removes the organic residues on the CNT films, but also satisfactorily protrudes the CNTs out of the electrode surface. The CNT cathodes prepared by the liquid method showed a turned-on field of $1.4\;V/{\mu}m$. The emission current density of them was about $3.1\;mA/cm^2$ at the electric field of $3\; V/{\mu}m$. The liquid method appears to be a promising surface treatment of CNT cathode for gated triode-type FEDs applications.

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Vertical Alignment Nematic Liquid Crystal Display with Patterned Electrode Using Positive Liquid Crystal Materials

  • Shin, Hun-Ki;Yoon, Tae-Hoon;Kim, Jae-Chang
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.499-501
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    • 2007
  • We propose a vertical-alignment liquid crystal display with patterned electrodes using a positive dielectric anisotropic liquid crystal. In this structure, the threshold and on-state voltages are reduced compared with previous vertical-alignment configuration with positive liquid crystal.

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Characterization of the Oxide Layer Formed on the Cu-Zr Based Metallic Glass during Continuous Heating

  • Lim, Ka-Ram;Kim, Won-Tae;Kim, Do-Hyang
    • Applied Microscopy
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    • 제42권3호
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    • pp.174-178
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    • 2012
  • In the present study, the oxidation behavior of $Cu_{50}Zr_{50}$ and $Cu_{46}Zr_{46}Al_8$ metallic glasses has been investigated using transmission electron microscopy with a particular attention on the oxidation behavior in the supercooled liquid state. Identification of the oxidation product after continuous heating treatment shows that in $Cu_{50}Zr_{50}$ metallic glass, $ZrO_2$ with the monoclinic structure forms on the supercooled liquid as well as on the crystallized matrix. On the contrary, in $Cu_{46}Zr_{46}Al_8$ metallic glass, $ZrO_2$ with the tetragonal structure forms on the supercooled liquid, but that with the monoclinic structure forms on the crystallized matrix. The result indicates that the $Cu_{50}Zr_{50}$ metallic glass exhibits far better oxidation resistance in the supercooled liquid state than the $Cu_{46}Zr_{46}Al_8$ metallic glass.