• 제목/요약/키워드: Mixing characteristics

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들께와 땅콩의 혼합 채유가 들기름의 이화학적 특성 및 산화안정성에 미치는 영향 (Effect of the Mixing Extraction of Perilla Seed and Peanut on Physicochemical Characteristics and Oxidative Stability of Perilla Oil)

  • 권용주;김충기;오현화
    • 한국식품영양과학회지
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    • 제28권6호
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    • pp.1212-1219
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    • 1999
  • The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.

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주파수 변조 분사가 횡단 유동장의 분무 특성에 미치는 영향 (Spray Characteristics of Modulated Liquid Jet Injected into a Subsonic Crossflow)

  • 이민철;김종현;구자예
    • 한국분무공학회지
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    • 제14권2호
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    • pp.59-64
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    • 2009
  • These experiments are close examination of spray characteristics that are continuous liquid jet and modulated liquid jet. The experiments were conducted using water, over a range of crossflow velocities from $42{\sim}l36\;m/s$, with modulation frequencies of $35.7{\sim}166.2\;Hz$. Between continuous crossflow jet and modulated cross-flow jet of penetration, breakup point, spray angle and macro spray shape are experimentally investigated with image analysis. In cross-flow field, main parameter of liquid jet for breakup was cross-flow stream rather than modulation effect. As oscillation of the periodic pressure that could make liquid jet moved up and down, the mixing efficiency was increased. Also, a bulk of liquid jet puff was detected at upper field of liquid surface. So, this phenomenon has a good advantage of mixing spray from concentration of center area to outer area. Because of modulation frequency, SMD inclination of the structured layer was evanescent. Cross-sectional characteristics of SMD at downstream area were non-structured distributions. Then cross-sectional characteristics of SMD size were about same tendency over a range that is effect of spray mixing. The tendency of volume flux value for various modulation frequency was same distribution. And volume flux was decreased when the modulation frequency increase.

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액체-액체 스월 동축형 인젝터의 분무특성 Part II : 리세스 형상에 따른 영향 (Spray Characteristics of a Liquid-Liquid Swirl Coaxial Injector Part II : Effect of Recess Configuration)

  • 김동준;김성혁;한풍규;윤영빈
    • 한국추진공학회지
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    • 제10권3호
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    • pp.9-17
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    • 2006
  • 본 연구는 케로신-LOX를 추진제로 하는 액체로켓엔진용 스월 동축형 인젝터의 리세스 길이에 따른 분무특성 파악을 목표로 하였다. 리세스 길이에 따른 두 추진제의 내부충돌현상에 의한 ripple의 형성과 감쇠가 인젝터 외부의 분무안정성에 영향을 미치므로 분무특성과 큰 연관성을 가진다. 또한, 리세스 길이가 증가함에 따라 평균액적크기는 증가하였으며, 혼합효율은 증가하다가 최대값에 도달한 후 다시 감소하는 경향성을 보였다.

고압 축소형 연소기의 연소 성능 특성에 관한 연구 (Combustion Performance Characteristics of a High Pressure Sub-scale Liquid Rocket Combustor)

  • 김종규;이광진;서성현;한영민;최환석
    • 한국추진공학회지
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    • 제11권5호
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    • pp.31-36
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    • 2007
  • 연소 압력이 70 bar인 고압 축소형 연소기의 연소성능 특성을 알아보았다. 모든 연소시험은 하드웨어의 손상 없이 성공적으로 이루어졌다. 분사기의 혼합특성과 분사기 배열이 연소성능에 큰 영향을 미치는 요소임을 파악하였다. 연소기의 특성속도는 외부 혼합보다 내부 혼합 분사기에서 더 크게 나타났으며 단위분사기당 추진제의 유량이 감소함에 따라 특성속도도 증가하였다. 추진제 매니폴드 및 연소실에서 측정된 압력 섭동은 평균 연소압력의 3% 이하로 연소안정성 기준치 보다 낮은 값을 보여 안정적인 연소기임을 보였다.

에멀젼연료의 분무거동특성에 관한 기초연구 (Basic Study of Spray-Behavior Characteristics of Emulsified Fuel)

  • 염정국;윤정환
    • 대한기계학회논문집B
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    • 제38권9호
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    • pp.763-771
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    • 2014
  • 본 연구는 에멀젼연료($diesel/H_2O_2$)의 분무거동특성에 관한 기초 연구로서 에멀젼연료를 제조하여 분무 거동특성에 영향을 주는 연료의 물성치(점도, 표면장력, 밀도)와 연료액적 증발특성을 조사하였다. 또한 에멀젼연료와 디젤연료의 거시적 분무거동특성인 분무선단도달거리, 분무각을 비교 분석하였다. 에멀젼연료의 교반 조건은 디젤 연료와 계면활성제 span 80, tween 80을 각각 9:1로 혼합한 유화제를 제작하여 사용 하였으며 과산화수소의 혼합비율은[EF(Emulsified Fuel)2, EF12, EF22, EF32, EF42, EF52, EF62, EF72, EF82, EF92]로 설정하였고, 분사압력은 400bar, 600bar, 800bar 및 1000bar로 설정하였다. 본 연구의 결과로서 연료의 점도는 과산화수소의 혼합비율이 증가할수록(EF52까지) 점도가 증가하나, 그 이후부터는 점도가 낮아져 기존의 디젤연료와 같은 점도를 가지게 된다. 이는 디젤의 혼합비율이 큰 EF52까지는 교반 시 수중유형(Water in Oil)이 생성되나 과산화수소의 혼합비율이 큰(EF52 이상) 에멀젼연료에서는 유중수형(Oil in Water)이 생성되기 때문이다. 또한 혼합비 변화에 따른 분무거동의 특성(분무선단도달거리, 분무각)의 변화는 크지 않았다.

무산화 직화로 버너의 연소특성이 강재표면의 산화에 미치는 영향 (Effects of Combustion Characteristics of the Burners for Non-Oxidizing Direct Fired Furnaces on the Oxidization of the Surface of Steel Plate)

  • 박홍수;유갑종
    • 대한기계학회논문집B
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    • 제23권3호
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    • pp.330-341
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    • 1999
  • An experimental study for the two types of burners used in the non-oxidizing direct fired furnaces of the heat treatment process for the cold rolled plate has been carried out to investigate the combustion characteristics and the oxidization of the surface of steel plate. A steep temperature gradient and entrainment of residual oxygen were found near the heating surface in the flame of the nozzle mixing burner which has strong swirl velocity component. It was concluded that the elimination of the residual oxygen and the increase of the temperature of combustion gas on the heating surface are needed to enhance the performance of the burners for application to the non-oxidizing direct fired furnaces.

제지용 면 펄프의 CMC 전처리 및 혼합 고해특성 연구 (Study on the Beating Properties of CMC Pre-treated and Mixed Cotton Linter Pulp)

  • 신현식;이진호;김덕기;박종문
    • 펄프종이기술
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    • 제46권4호
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    • pp.11-20
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    • 2014
  • The objective of this study was to investigate the beating properties of two types of cotton pulps such as "cotton lint mixed pulp" and "cotton linter pulp". In order to improve refining characteristics, the effects of carboxymethyl-cellulose (CMC) pre-treatment, mixing ratio changes of cotton lint mixed pulp and cotton linter pulp, and refining load changes were analyzed. In mill application, it was possible to improve the refining characteristics and maintained the strength properties of the paper by applying increasing ratio of cotton linter pulp mixing and controlling the refining methods.

PREDICTING PARAMETERS OF TRANSIENT STORAGE ZONE MODEL FOR RIVER MIXING

  • Cheong, Tae-Sung;Seo, Il-Won
    • Water Engineering Research
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    • 제4권2호
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    • pp.69-85
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    • 2003
  • Previously developed empirical equations used to calculate the parameters of the transient storage model are analyzed in depth in order to evaluate their behavior in representing solute transport in the natural streams with storage zone. A comparative analysis of the existing theoretical and experimental equations used to predict parameters of the transient storage (TS) model is reported. New simplified equations for predicting 4 key parameters of the TS model using hydraulic data sets that are easily obtained in the natural streams are also developed. The weighted one-step Huber method, which is one of the nonlinear multi-regression methods, is applied to derive new parameters equation. These equations are proven to be superior in explaining mixing characteristics of natural streams with the transient storage zone more precisely than the other existing equations.

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섬유혼합 점토의 비배수 강도 특성에 대한 연구 (Study on the Undrained Strength Characteristics of Fiber Mixed Clay)

  • 박영곤;장병욱
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 1998년도 학술발표회 발표논문집
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    • pp.382-387
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    • 1998
  • Triaxial compression tests were run to study on the undrained strength characteristics of fiber mixed kaolin clay(Hadong). The influence of various test parameters such as amount and aspect ratio(ratio of length to diameter) of fiber, confining stress was also investigated. Test results showed that the increase in aspect ratio was increased in deviator stress at failure, but no effect on pore water pressure at failure. Deviator stress at failure was also increased at 0.5% mixing ratio(weight fraction of fiber to that of soil solid) of fiber but it was, thereafter, decreased and wits reached to constant after 2% mixing ratio. On the contrary, Pore water pressure at failure was increased as mixing ratio of fiber was greater than 1%. Deviator stress and pore water pressure of both clay and fiber mixed clay(FMC) at failure were increased as confining stress was increased. Deviator stress of FMC at failure was about 10% larger than that of clay, but pore water pressure of FMC at failure was almost similar to that of clay.

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