• Title/Summary/Keyword: Spray Development

검색결과 674건 처리시간 0.029초

충돌분무와 액막의 열전달 해석모델을 고려한 범용 열/유체 프로그램 NUFLEX의 개발 (DEVELOPMENT OF A GENERAL PURPOSE THERMO/FLUID FLOW ANALYSIS PROGRAM NUFLEX WITH WALL IMPINGEMENT AND HEAT TRANSFER ANALYSIS MODEL OF LIQUID FILM)

  • 김현정;노경철;유홍선;허남건
    • 한국전산유체공학회지
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    • 제13권2호
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    • pp.68-72
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    • 2008
  • NUFLEX is a general purpose thermo/fluid flow analysis program which has various physical models including spray. In NUFLEX, spray models are composed of breakup and collision models of droplet. However, in case of diesel engine, interaction between wall-film and impingement model considering heat transfer is not coded in NUFLEX. In this study, Lee & Ryou impingement & wall-film model considering heat transfer is applied to NUFLEX. For the verification of this NUFLEX program, numerical results are compared with experimental data. Differences of film thickness and radius between numerical results and experimental data are within 10% error range. The results show that NUFLEX can be used for comprehensive analysis of spray phenomena.

Development of Paint-type and Spray-type Electromagnetic Wave Absorbers

  • Song Jae-Man;Kim Dong-Ii;Choi Jeung-Hyun;Jeung Jae-Hyun;Kim Ki-Man
    • Journal of electromagnetic engineering and science
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    • 제5권4호
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    • pp.172-175
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    • 2005
  • Sometimes, it is more convenient to use paint-type and spray-type EM wave absorbers than bulk-type or sheet-type. Thus, in this paper, we prepared paint-type and spry-type EM wave absorbers. The proportion of ferrites to paints, particle size of magnetic material, and kinds of paint should be considered to prepare a superior paint-type EM wave absorber. There is no big gap between spray-type and paint-type in EM wave absorption of EM wave absorbers prepared with same composition.

경량 단조 피스톤 기술 개발 (Development of Forged Piston for Weight-Reduction)

  • 홍은지;강희삼
    • 한국자동차공학회논문집
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    • 제25권1호
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    • pp.111-115
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    • 2017
  • This forged piston is proposed with a lighter weight and higher durability than a gravity casting piston for gasoline engines. However, a forged piston is very difficult to develop and mass-produce due to lack of basic technologies such as design, material and forging technique. First, we benchmarked existing forged pistons according to database design parameters. Second, we evaluated two solidification processes, continuous casting and spray forming, to produce heat-resistant alloy billets for forging. The spray forming process gives better mechanical properties at all temperatures, particularly at elevated temperatures except when poor formability is present. We used DEFORM simulation to determine the optimum process condition with billet from spray forming and successfully commercialized it with LF Sonata HEV.

벽면에 충돌하는 분무의 미립화에 관한 수치적 모델 (A Numerical Model for Atomization of an Impinging Spray on the Wall)

  • 조미옥;허강열
    • 한국분무공학회지
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    • 제2권1호
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    • pp.36-45
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    • 1997
  • A spray-wall impingement model for fuel sprays is proposed and implemented as a module into the KIVA-POSTECH code. The model is based on the single droplet experiments. The droplet behaviors after impingement are determined from experimental correlations. Different behaviors of impinged droplets depend on the wall temperature and the critical temperature of the fuel. Fuel film formation is taken into account so that the model can be applicable to any wall temperature and injection conditions. Computational results on a normal and on inclined wall are in good agreement for the spray shape and penetration. More validation against experiments and development of the heat transfer model are needed for further improvement.

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피스톤 방식의 고온·고압 뿜칠장치를 이용한 방수 시공 기술 공법에 관한 연구 (An Study on the Development of Waterproofing Execution Technology With high Temperature and Spray Equipments of Piston Type)

  • 문유석;최은규;최성민;곽규성;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2008년도 추계 학술논문 발표대회
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    • pp.7-12
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    • 2008
  • We constructed Seal type waterproofing with adhesive and swelling properties in the field of construction work as yet. But we have many problems of seal type waterproofing with adhesive and swelling properties for construction. Because it has high viscosity, so wokers are too adhered for the work. So, we developed and applied about the high temperature and spray equipments of piston type better than before. We able to be expect that cost reduction and increase construction ability by high temperature and spray equipments of piston type.

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A Numerical Study on Heat Transfer Characteristics in a Spray Column Direct Contact Heat Exchanger

  • Kim, Chong-Bo;Kang, Yong-Heack;Kim, Nam-Jin;Hur, Byung-Ki
    • Journal of Mechanical Science and Technology
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    • 제16권3호
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    • pp.344-353
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    • 2002
  • A reliable computational heat transfer model has been investigated to define the heat transfer characteristics of a spray column direct contact heat exchanger, which is often utilized in the process involving counterflows for heat and mass transfer operations. Most of the previous studies investigated are one-dimensional unsteady solutions based on rather fragmentary experimental data. Development of a multidimensional numerical model and a computational algorithm are essential to analyze the inherent multidimensional characteristics of a direct contact heat exchanger. The present study has been carried out numerically and establishes a solid simulation algorithm for the operation of a direct contact heat exchanger. Operational and system parameters such as the speed and direction of working fluid droplets at the injection point, and the effects of aspect ratio and void fraction of continuous fluid are examined thoroughly as well to assess their influence on the performance of a spray column.

충돌분무 액막의 열전달 해석모델을 고려한 범용 열/유체 프로그램 NUFLEX의 개발 (Development of a general purpose thermo/fluid flow analysis program NUFLEX with heat transfer analy sis model of impinging liquid film)

  • 김현정;노경철;유홍선;허남건
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.71-74
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    • 2008
  • NUFLEX is a general purpose thermo/fluid flow analysis program which has various physical models including spray. In NUFLEX, spray models are composed of breakup and collision models of droplet. However, in case of diesel engine, interaction between wall-film and impingement model considering heat transfer is not coded in NUFLEX. In this study, Lee & Ryou impingement & wall-film model considering heat transfer is applied to NUFLEX. For the verification of this NUFLEX program, numerical results are compared with experimental data. Differences of film thickness and radius between numerical results and experimental data are within 10% error range. The results show that NUFLEX can be used for comprehensive analysis of spray phenomena.

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연료유 스크러버 노즐의 스월베인 구조변화에 따른 분무특성의 수치해석적 연구 (Study of spray characteristics according to the variation of swirl vane geometry for Fuel oil scrubber nozzles)

  • 김인철;이경우;이영호
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2012년도 전기공동학술대회 논문집
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    • pp.203-203
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    • 2012
  • The Recovery facility, the scrubber is a collection device that injects liquid into the gas with the suspended particles using a spray nozzle. The liquid used is generally water. For the development of the design technology of a high efficiency scrubber, the spray characteristics according to the variation of the scrubber nozzle swirl vane was studied.

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세탄가 향상 혼합 연료에 따른 디젤 연료의 분무 및 연소특성에 관한 연구 (The Spray and Combustion Characteristics by the Ratio of Cetane Number Enhancing Additives in Diesel)

  • 김지훈;이성욱;이한승;최정황;이영철;조용석
    • 한국분무공학회지
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    • 제14권2호
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    • pp.84-89
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    • 2009
  • In this research, combustion and spray characteristics were investigated experimentally in a constant volume chamber by applying different composition rates of octane number in diesel fuel to a common-rail system. For the visualization, the experiment was carried out under different injection pressures and different cetane number. The test was done by three different types of diesel fuels, the different composition rates of cetane number in diesel fuel and HBD. In summary, this research aims to investigate the combustion characteristics in the application of fuels and compare the results with performance of conventional diesel fuel. This experimental data may provide with fundamentals of the development of diesel engines in future.

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FDS를 이용한 교번식 미분무방식의 소화 성능 분석 (Analysis for fire suppression efficiency of intermittent water spray pattern with FDS)

  • 지문학;이병곤
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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    • pp.200-203
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    • 2008
  • Water mist fire suppression system utilizes the fire suppression features such as cooling of fire source, dilution of ambient oxygen, and shielding of radiation heat with the evaporation of microscopic water droplets. The momentum of water mist is relatively low and the infiltration of water mist to the fire source is not effective. In addition to lower penetration force, the evaporated water vapor is liable to decline to limited portion of fire source due to its light weight and sparse density. On the other hand, the cycling water mist system is expected to improve the penetration force of water mist as well as the dilution coverage capability with the stratified spray characteristics. At this paper we present the analyzed fire suppression capability of intermittent water spray pattern by use of FDS which is computational fire dynamics fire model. We expect this analysis shall be supportive to the development of the prototype of water mist nozzle.

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