• 한국분무공학회지
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• 제11권4호
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• pp.205-211
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• 2006

Impinging angle, impinging distance, length eve. diameter and injection pressure of a triplet injector were tested to evaluate the spray characteristics injected by liquid/gas combinations. Two different kinds of unlike triplet sprays were produced by changing the gas and liquid feed lines. One was the G-L-G(Gas-Liquid-Gas) type, and the other was L-G-L(Liquid-Gas-Liquid) type. Spray angles were wider with the G-L-G type than with L-G-L type. Mass distributions in spray were obtained with a, mechanical patternator. Mass distributions were not circular but elliptical distributions. When the range of mechanical patternator to injector decreased, mass distributions were more concentrated in the center region.

• 한국항공운항학회지
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• 제15권4호
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• pp.1-8
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• 2007

Spray characteristics of a unlike triplet injector were investigated experimentally. Spray images and SMD of droplet were measured to evaluate the spray characteristics injected by liquid/gas combinations. G-L-G(Gas-Liquid-Gas), L-G-L(Liquid-Gas-Liquid) type of injector were used by changing the gas and liquid feed lines. The SMD graph shows that the droplet sizes decrease in the out of radial direction at a fixed gas Reynolds number. The SMD value of decreasing tendency shows that the more ethyl alcohol ratio increase, the more SMD value decrease.

• Korean Chemical Engineering Research
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• 제56권2호
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• pp.186-190
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• 2018

For the first time, the characteristics of solid circulation rate ($G_S$) were investigated in a three-phase (gas-liquid-solid) viscous circulating fluidized bed (TPCFB). The solid circulation rate was controlled separately by adjusting the experimental apparatus as well as operating variables. Effects of primary and secondary liquid velocities ($U_{L1}$ and $U_{L2}$), gas velocity ($U_G$), particle size ($d_p$), height of particles piled up in the solid recycle device (h), and viscosity of continuous liquid media (${\mu}_L$) on the value of $G_S$ were determined. The experimental results showed that the value of $G_S$ increased with increases in the values of $U_{L1}$, $U_{L2}$, h and ${\mu}_L$, while it decreased with increasing $U_G$ and $d_p$ in TPCFBs with viscous liquid media. The values of $G_S$ were well correlated in terms of dimensionless groups within this experimental conditions.

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.99-105
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• 2003

A liquid-liquid extraction followed by evaporative concentration method was used to determine the concentration of normal, or straight chain, saturated hydrocarbons (NSH) $(C_{10}\;to\;C_{24})$ and polycyclic aromatic hydrocarbons (PAH) here defined as: fluorene, anthracene, pyrene, chrysene and perylene, in the Buriganga River water of Bangladesh. Samples were collected from 5 and 25 cm depth of water at the southern, middle and northern parts of the river at Postogolla, Sadarghat and Sowarighat stations. Hydrocarbons were extracted from 450 mL of water into 75 mL n-hexane and then concentrated into 1 or 2 mL solution by evaporation. These solutions were analyzed by gas chromatography. The highest and lowest concentrations were determined as $257\;{\mu}gL^{-1}\;for\;C_{13}\;and \;0.24\;{\mu}g\;L^{-1}\;for\;C_{22}$ at 5 ㎝ depth of water, at the northern part of the Sowarighat and southern part of the Postogolla, respectively. This method could allow the analysis of water for $C_{22}$ as low as $0.24\;{\mu}g\;L^{-1}$.

• Korean Chemical Engineering Research
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• 제46권3호
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• pp.521-528
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• 2008

중공사막 접촉기에 적절한 PVDF 중공사막을 상전이 공정에 의하여 제조하였으며, SEM 과 기체투과도에 의하여 그 특성을 분석하였다. 벤치규모 중공사막 접촉기에서 $SO_2$ 제거를 위한 흡수제는 수산화나트륨 수용액을 사용하였다. 기체는 shell side, 액체는 lumen side로 흐르는 counter-current로 실험하였으며, 흡수제의 농도, 기체의 유속, 액가스비, 유입 $SO_2$ 농도에 따른 영향을 알아보았으며, 수학적 모델링에 의해 막 물질전달계수($k_m$)를 측정하였다. 흡수제의 농도와 액기비가 증가함에 따라 기-액 계면에서 충분한 알칼리도가 제공되므로, 액체막 저항이 감소하며, 총괄물질전달 용량계수는 증가하였다. 기체유속이 증가함에 따라 기체막저항은 감소하게 되므로 총괄물질전달 용량계수는 증가하였다.

• Korean Chemical Engineering Research
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• 제49권5호
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• pp.582-587
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• 2011

점성액체 기포탑에서 기포, wake 및 연속액상들의 체류량 특성을 고찰하였다. 기포탑의 직경(0.051, 0.076, 0.102 and 0.152 m ID), 기체 유속(0.02~0.16 m/s) 그리고 연속액상의 점도(0.001~0.050 $Pa{\cdot}s$)가 기포, wake 및 연속액상의 체류량에 미치는 영향을 검토하였다. 기포, wake 그리고 연속액상들은 이중 전기 저항탐침방법에 의하여 성공적으로 구별할 수 있었다. 압축된 여과공기와 물 또는 CMC 수용액을 각각 기체와 연속액상으로 사용하였다. 기포탑에서 기포와 wake 상들을 연속적으로 검침하기위해 자료수집장치(DT 2805 Lab Card)와 컴퓨터를 사용하였다. 탐침 써키트로부터 수집된 아날로그 자료는 디지털 자료로 변환되었으며, 이들 자료를 이용하여 기포탑에서 상승하는 단일기포 뿐만이 아니라 다중기포들의 후면에서 wake 상을 검침할 수 있었다. 기포와 wake 상의 체류량은 각각 기포탑의 직경과 연속액상의 점도가 증가함에 따라 감소하였으나 연속액상의 체류량은 증가하였다. 그러나, 기포와 wake의 체류량은 각각 기체 유속이 증가함에 따라 증가한 반면 연속액상의 체류량은 감소하였다. wake 상 체류량에 대한 기포 체류량의 비율은 기포탑의 직경 또는 기체의 유속이 증가함에 따라 감소한 반면 연속액상의 점도가 증가함에 점성액체 기포탑에서 기포, wake 그리고 연속액상의 체류량은 본 연구의 실험범위에서 다음과 같은 실험변수의 상관식으로 나타낼 수 있었다. ${\varepsilon}_B=0.043D^{-0.18}U_G^{0.56}{\mu}_L^{-0.13}$, ${\varepsilon}_W=0.003D^{-0.85}U_G^{0.46}{\mu}_L^{-0.10}$, ${\varepsilon}_C=1.179D^{0.09}U_G^{-0.13}{\mu}_L^{0.04}$.

• Nuclear Engineering and Technology
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• 제7권1호
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• pp.3-8
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• 1975

만성 하악골염, 유행성출혈, 만성 신부전 및 간 경변증을 가진 환자의 혈청중에 포함된 여러가지 종류의 유리아미노산의 정량분석을 gas-liquid chromatography (G. L. C.)로 측정하였고, 건강인들의 유리아미노산의 정량과 비교한 결과 환자의 종류에 따라서 혈청중에 포함된 유리아미노산의 양에 차이가 있음을 발견 하였다.

• 공업화학
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• 제17권5호
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• pp.509-516
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• 2006

Rushton turbine, paddle and propeller 임펠러 등 표준적인 임펠러가 부착된 기-액-고 3상교반조에서 고-액간 물질이동계수 $k_L$를 측정하였다. 표준적인 임펠러들에 대한 부유화한계회전수 $N_{js}$는 임펠러 높이와 가스유속에 따라 변했다. 입자부유가 통기에 의존한 Rushton turbine 임펠러의 물질이동계수는 Pgv에만 상관하였다. Rushton turbine, paddle and propeller 임펠러에 대한 물질이동계수 $k_L$은 임펠러의 종류에 의하지 않고 임펠러 위치에 영향을 받았다.

• Journal of Advanced Marine Engineering and Technology
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• 제29권4호
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• pp.377-383
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• 2005

This paper deals with the flow characteristics of air-water two-phase flow in a vertical tube of 10mm I.D. and 600mm in length at an adiabatic condition. The obtained experimental data were covered with the liquid superficial velocity ranging from 0.095m/s to 2.56m/s. and the gas superficial velocity ranging from 0.032m/s to 21.08m/s. The effects of the gas and liquid superficial velocity on the flow pattern transitions, frictional pressure drop, and film thickness and gas-liquid interface roughness were also examined. It was found that the film thickness increased and the liquid film wave length was more longer with the liquid superficial velocity $j_L$ increasing at $j_G$ constant. It was also showed that the frictional pressure drops were experienced in three regions. namely increasing region(bubbly flow), decreasing region (Taylor bubble and slug flows) and re-increasing region (annular flow).

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3805-3809
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• 2012

Results for molecular dynamics simulation method of small liquid drops of argon (N = 1200-14400 molecules) at 94.4 K through a Lennard-Jones intermolecular potential are presented in this paper as a preliminary study of drop systems. We have calculated the density profiles ${\rho}(r)$, and from which the liquid and gas densities ${\rho}_l$ and ${\rho}_g$, the position of the Gibbs' dividing surface $R_o$, the thickness of the interface d, and the radius of equimolar surface $R_e$ can be obtained. Next we have calculated the normal and transverse pressure tensor ${\rho}_N(r)$ and ${\rho}_T(r)$ using Irving-Kirkwood method, and from which the liquid and gas pressures ${\rho}_l$ and ${\rho}_g$, the surface tension ${\gamma}_s$, the surface of tension $R_s$, and Tolman's length ${\delta}$ can be obtained. The variation of these properties with N is applied for the validity of Laplace's equation for the pressure change and Tolman's equation for the effect of curvature on surface tension through two routes, thermodynamic and mechanical.