• 물과 미래
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• 제6권1호
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• pp.5-12
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• 1973

A simple regression formula for estimating the lake evaporation rate from the copper-plated pan (diameter 20cm, height 10cm) is derived. A comparison with other formulae indicates that the formula is more accurate than others. An annual map of man evaporation in Korean peninsula has been prepared using the relation. It demonstrates the areal average distribution of mean annual evaporation from a free water surface with no heat storage effect and avected energy owing to differences in the temperature of in-and outflow. The mean annual ratio of the lake to the copper-plated pan evaporation is found to be 0.64. The ratio varies with local conditions from 0.62 to 0.66, and hence it can be considered fairly uniform. However the seasonal variation of the ratio appears to be rather significant. It changes from the lowest of 0.61 to the highest of 0.75.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.335-340
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• 2005

Nonlinear and forced oscillations of supported viscous droplet were focused in the present study. The droplet has a free contact line with solid plate and inviscid fluid. Natural frequencies of a pendant droplet have been investigated experimentally by imposing the acoustic wave while the frequency is being increased at a fixed amplitude. The evaporation was observed at atmosphere pressure. The droplet was recorded throughout the entire evaporation process and transient variations of the volume was measured. The evaporation process of oscillating droplet with thermofoil has been also observed to investigate analyzing the resonance effect on the thermal characteristics of droplet. It is found that a pendant droplet shows the resonant behaviors at each mode similar to the theoretical analysis. During imposing the acoustic wave, the pendant droplet makes a rotating motion in its longitudinal axis which is a new shape oscillation mode. The evaporation rate of a pendant droplet at resonant frequency is significantly enhanced.

• 대한기계학회논문집B
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• 제32권8호
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• pp.567-573
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• 2008

The conventional refrigeration system is composed of a compressor, condenser, receiver, expansion valve or capillary tube, and an evaporator. The refrigeration system used in this study has additional expansion valve and evaporator along with an evaporation pressure regulator(EPR) at the exit side of the evaporator. The two evaporators can be operated at different temperatures according to the opening of the EPR. The experimental results obtained using the refrigeration system with parallel control of evaporation pressure are presented and the performance analysis of the refrigeration system with two evaporators is conducted.

• 대한토목학회논문집
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• 제30권3B호
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• pp.243-255
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• 2010

본 연구에서는 pan 증발량 분포와 추세를 분석하였다. 이를 위하여 전국 56개 기후관측지점에서 1973년부터 1990년까지 의 pan 증발량 자료를 수집하여 분석을 실시하였다. 분석을 위하여 계절적 영향을 고려하여 1월, 4월, 7월 그리고 10월의 월평균 일별과 연평균 일별 pan 증발량 추세를 분석하였다. 연구결과 연평균 일별 pan 증발량은 56개 연구지역 중에서 38개 연구지역에서 감소추세를 보이고 있고, 1월 평균 일별 pan 증발량의 경우 33개 연구지역에서 pan 증발량 감소추세를 보이고 있다. 4월의 경우 38개 지역에서 증가추세를 보이고, 7월의 경우 47개 지역에서 감소추세를 보여서, 전반적으로 감소추세를 보이고 있다. 10월의 경우 35개 지역에서 증가추세를 보여서 전반적으로 증가추세를 보이고 있다. 따라서 전반적으로 연별과 1월, 7월은 pan 증발량이 감소추세를 보이고, 4월과 10월은 증가추세를 보이고 있다. 또한 인근에 위치한 권역별로도 다른 추세를 보이는 것으로 나타나서 지리지형적 요인이 pan 증발량 추세에 영향을 미치는 것으로 판단된다. 11개 기후관측지점에서 1973년부터 2006년까지의 pan 증발량 자료와 기후요소자료를 수집하여 추세분석을 실시한 결과, 기온, 상대습도 그리고 풍속추세는 연별이나 월별 pan 증발량 추세와 서로 같거나 또는 상이한 경향을 보이나, 일사량 추세는 연 및 월별 모두에서 pan 증발량 추세와 동일한 경향을 보이고, 강수량 추세는 연 및 월별 모두에서 pan 증발량 추세와 상반된 경향을 보였다.

• Korean Chemical Engineering Research
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• 제60권1호
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• pp.25-33
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• 2022

본 연구에서는 흑액 증발공정에 소비되는 스팀의 절감량을 예측하기 위해 증발기 수에 따른 다중 효용 증발공정 모델을 개발하였다. 개발한 공정 모델은 흑액의 예열 및 증발 과정으로 구성되어 있고, 스팀 사용량을 예측하기 위해 가상의 재비기가 추가되었다. 시뮬레이션 결과, 2중 효용 증발기에서 스팀 사용량은 48.9% 감소하였고, 증발기 수가 증가함에 따라 스팀 사용량이 감소하여 8중 효용 증발기에서 최대 76.5% 감소함을 확인하였다. 시뮬레이션 결과를 증발기 수에 따른 포화증기의 잠열 회수량, 스팀 사용량, 각 증발기의 포화증기 생산량으로 분석하여 최적의 증발기 수 도출을 위한 방안을 제시하였다.

• 한국전기전자재료학회논문지
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• 제22권11호
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• pp.956-960
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• 2009

The characteristics of organic films can be affected by the temperature of evaporation source because the temperature of evaporation source has an effect on substrate temperature during OLED fabrication process using the thermal evaporation. To investigate the characteristics of OLED devices fabricated by using thermally damaged organic films, I-V-L and half life-time in OLED devices fabricated with various substrate temperatures were measured. During emission layer(EML) evaporation, OLED devices with a structure of ITO(100 nm)/ELM200(50 nm)/NPB(30 nm)/$Alq_3$(55 nm)/LiF(0.7 nm)/Al(100 nm) were fabricated at various substrate temperatures(room temperature, $30^{\circ}C$, $40^{\circ}C$, and $50^{\circ}C$). The characteristics of current density and luminance versus applied voltage in OLED devices fabricated shows that many electrical currents flowed and high brightness appeared at low voltage, but that the lifetime of OLED devices dropped suddenly. This phenomenon explained that the crystallization of $Alq_3$ thin film appeared owing to the substrate heating during evaporation.

• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.274-277
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• 2007

In this study, liquid crystal(LC) aligning capabilities for homeotropic alignment on the $SiO_x$ thin film by electron beam evaporation method were investigated. Also, the control of pretilt angles and thermal stabilities of the nematic liquid crystal(NLC) treated on $SiO_x$ thin film were investigated. A high pretilt angle of about $86.5^{\circ}$ was obtained, and also the suitable pretilt angle of the NLC on the $SiO_x$ thin film at $10{\sim}50nm$ thickness with e-beam evaporation can be achieved. The uniform LC alignment and good thermal stabilities on the $SiO_x$ thin film surfaces with electron beam evaporation can be achieved. It is considered that the LC alignment on the $SiO_x$ thin film by electron beam evaporation is attributed to elastic interaction between LC molecules and micro-grooves at the $SiO_x$ thin film surface created by evaporation.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.240-241
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• 2005

The experiments were conducted without oil in a closed refrigerant loop which was driven by a magnetic gear pump. The main components of the refrigerant loop are a receiver, a variable-speed pump, a mass flow meter, a pre-heater and evaporator(test section). The test section was made of a horizontal stainless steel tube with the inner diameter of 4.57 mm, and length of 4 m. The experiments were conducted at mass flux of 200 to 700 kg/$m^2s$, saturation temperature of 0$^{circ}C$ to 20$^{circ}C$, and heat flux of 10 to 30 kW/$m^2$. The test results showed the evaporation heat transfer of $CO_2$ has great effect on more nucleate boiling than convective boiling. The evaporation heat transfer coefficients of $CO_2$ are highly dependent on the vapor quality, heat flux and saturation temperature. In comparison with test results and existing correlations, correlations failed to predict the evaporation heat transfer coefficient of $CO_2$, therefore, it is necessary to develop reliable and accurate predictions determining the evaporation heat transfer coefficient of $CO_2$ in a horizontal tube.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 춘계학술발표강연 및 눈문개요집
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• pp.70-70
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• 1999

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1462-1465
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• 2004

A new method to fabricate metal electrodes on side wall of the microchannel is presented. Coulter counter allows to count the number of cell passing through the microchannel by detecting impedance variation between two electrodes. The relative position of two electrodes is important for sensitivity of impedance measurement. 100nm thick Al electrodes are deposited on the channel side wall by means of shadow evaporation.