• 한국식품과학회지
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• 제37권2호
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• pp.164-170
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• 2005

미생물유래의 중합화효소(microbial transglutaminase, MTGase)를 이용하면 식품 단백질의 기능특성을 향상시키는 것이 가능하다. 본 연구에서는 MTGase를 이용, 동물성 단백질인 ${\beta}$-casein 및 식물성 단백질인 11S globulin의 동종 혹은 이종간을 bio-hybrid시킴으로써 단백질의 기능특성을 향상시키고자 하였다. 즉, SDS-PAGE에 의한 susceptibility 확인, particle size 분석 및 Reddy and Foster 방법에 의한 유화안정성(emulsion stability) 실험, 그리고 유화안정성에 영향을 주는 bio-hybrid된 단백질이 어떤 형태로서 안정성에 영향을 미치는지 주사형 전자현미경(SEM)을 이용하여 유적(oil droplet)에 결합된 단백질을 고배율로 분석하였다. SDS-PAGE에 의해 동종 흑은 이종의 단백질간의 가교결합이 형성되었으며, 특히 이종간의 결합은 그 밴드가 약하게 형성되었으며 oligomer의 형태를 나타내었다. 또한 유화안정성은 동종간에서는 ${\beta}$-casein이 우수하였으며, glycinin은 안정성이 거의 없는 것으로 나타났다. 그러나, 두 단백질 이종간의 안정성은 glycinin보다 더 우수하였다. 전자현미경 사진에서는 유적에 bio-hybrid된 단백질이 고르게 분포될수록 안정성이 더 우수한 것으로 판단되었다.

• 한국분무공학회지
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• 제6권1호
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• pp.9-17
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• 2001

The effect of air entrainment in twin-fluid spray structure is investigated experimentally by varing the amount of itemizing air. The air entrainment is expected to affect on droplet size and velocity, droplet number density, turbulent kinetic energy and vorticity. PDA(Phase Doppler Anemometer) and PIV(Particle Image Velocimetry) system are used to measure those important factors in analyzing spray structure. The results show that spray structure consists of three distinctive regions ; the atomizing region near nozzle, characterizing strong convective effect, the central core region where droplets are accelerated, and the spray sheath region where droplets are decelerated due to air entrainment. The local air entrainment rate is largest near nozzle, characterizing strong turbulent kinetic energy and vorticity but deceases along axial distance.

• 한국분무공학회지
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• 제7권4호
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• pp.23-31
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• 2002

In this study, the sizes and velocities of droplets in sprays were measured by image processing method from digital images of local region of sprays. The morphological method based on the Euclidean distance transform, Watershed separation, and perimeter image was adopted for the recognition and separation of overlapped particles. The match probability method was used for the particle tracking and pairing. The measurement results show that the present method may be reliable for the analysis of the motion and distribution of droplets produced by spray and atomization devices.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.691-694
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• 2008

Spray characteristics of the APU simplex fuel nozzle are investigated. Four flight conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power are used as spray experimental conditions. Spray visualization was performed by using ND-YAG laser. Droplet size and velocity were measured by using PDPA(Phase Doppler Particle Analyzer) system. From the test result, SMD is 100 ${\mu}$m�� and velocity is 10 m/s at 20,000 ft idle condition. In this condition, flame unstability could be occurred due to the higher drop diameter. Therefore it is necessary to decrease the droplet diameter in the high altitude condition.

• Agricultural and Biosystems Engineering
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• 제3권1호
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• pp.44-54
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• 2002

A brief review of current status in the field of agricultural spray and future research challenges are presented. Researches on the pesticides sprays, pollen sprays, postharvest sprays, and biological control agent sprays among the various applications of agricultural spray were selected and reviewed. In the agrochemical sprays, the techniques to increase the deposition such as electrospray and reduce the drift such as introductions of drift retardants and of mechanical means are reviewed. The introduction of mechanical means includes low drift, air-assisted, air inclusion, shield or shroud assisted and pulse flow nozzles. For flat fan nozzles, the data of breakup length and thickness of liquid sheet are essential to understand the atomization processes and develop the transport model to target In the air-assisted spray technology to reduce drift, further works on the effect of application height on drift and air assistance on droplet size should be followed. In addition, methods for quantifying the included air in the air inclusion techniques are required. The atomization characteristics of biopesticides spray are not being elucidated and the formulations of biopesticides should be taken into account the spray characteristics of existing nozzle and sprayer. A few researches on the droplet size of fallout can be found in the literature. A combined technology with electrostatic method into one of method for the reduction of drift may be an effective strategy for increasing deposition and reducing drift. Only an integrated approach involving all stakeholders such as engineers, chemists, and biologists, etc. can result in improved application of agricultural spray.

• 대한기계학회논문집
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• 제15권6호
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• pp.2147-2159
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• 1991

본 연구에서는 가장 다순한 내부혼합형 이류체분사노즐의 기류속도, 액체유량, 노즐직경 및 혼합길이, 기액접촉각을 변화시켜 평균입경(SMD), 분무각, 입도분포, 분 무분사량분포 등을 조사하여 노즐형상에 따른 분무특성의 변화를 자세히 밝혀, 분무특 성을 조절할 수 있는 이류체분사 노즐의 설계에 대한 기초적 자료를 제시하고자 한다.

• Journal of Biosystems Engineering
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• 제18권2호
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• pp.100-109
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• 1993

The aim of this study was to provide the reasonable data for design of the nozzle which produces finer droplets on the same level of the effective travel distance or which transports droplets to the farther target on the reasonable atomization in comparison with the commercial nozzles being used much in Korean rural areas. Newly designed twin-fluid atomizers with some commercial nozzles were tested in this study, and their results were as follows : 1. The characteristics of the spray deposit distribution of No.1 nozzles for farther target were nearly same in the near or nearer travel distance less than 8m. Therefore it was reasonable to combine the characteristics of the spray deposit distributions of No.2 and No.3 nozzles to those of No.1 nozzle. 2. The effective travel distance was increased with increase of the sectional area of the jet ligament, and the maximum effective travel distance was reached to about 17m. 3. The droplet size was increased with increase of the sectional area of the jet ligament, and the maximum droplet size was produced in the front of the point of the maximum spray deposit distribution. 4. The atomization was excellent in the twin-fluid atomizer in comparison with the hydraulic atomizer and also the effective travel distances were nearly same level in both atomizers.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.815-820
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• 2009

Binary nanoemulsions which are defined as the, oil-droplet suspensions in binary solution ($H_2O$/LiBr), are developed to enhance the heat and mass transfer performance of absorption refrigeration systems. In this study, a novel two-step method is proposed to prepare the stable oil-in-binary solution (O/S) emulsion. Polymer is used as a steric stabilizer to stabilize the oil-droplets in a strong electrolyte ($H_2O$/LiBr). It is found that the thermal conductivity of the binary nanoemulsion is inversely proportional to the emulsion size while the concentrations of oil and $H_2O$/LiBr are less dominant for the thermal conductivity of binary nanoemulsions.

• 한국분무공학회지
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• 제5권3호
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• pp.27-36
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• 2000

In this study, spray characteristics of a dual airblast atomizer are addressed. Three dimensional characteristics of a dual airblast atomizer with air swirl are measured to provide the significant data. The liquid flow rate was fixed at 0.06 kg/min, and atomizing air was controlled at the liquid-air mass ratio of 4.0. The performance of the spray with co-swirl and counter-swirl flow was investigated at each point in the developed spray region using a three-component phase Doppler particle analyzer. This instrument was also used to evaluate the concentration profiles. The three dimensional mean velocity were investigated of present flow characteristics of the dual airblast atomizer. In addition, drop size distributions, mean droplet size profile, and droplet concentration were analyzed to understand atomization characteristics. This experimental results can be conveniently utilized for the preliminary design of gas turbine engines for aircraft.

• 한국분무공학회지
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• 제10권4호
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• pp.1-7
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• 2005

The purpose of this study is to investigate the effect of swirler vane angle and the aspect ratio of swirl chamber of nozzle on the characteristics of single spray. The characteristics of sprat's have been investigated by measuring the spray angle, droplet size and velocity Visualization of spray was conducted to obtain the spray angle and breakup process. The spray characteristics such as droplet size and velocity were measured by Phase Doppler Anemometry(PDA). It was found that the spray angle was increased with increasing the swirler angle. For both sprays, the axial velocity and SMD were decreased with increasing the swirler vane angle. It was also shown that the axial velocity and SMD were decreased with increasing the aspect ratio of swirl chamber The effect of vane angle un the spray characteristics was greater than the aspect ratio of swirl chamber for single spray.