• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.2
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• pp.211-218
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• 2002

It has been investigated for the temperature profile in a planar evaporator of micro-cooler subject to a uniform heat flux prior to tole initiation of boiling. The results of the analysis allow for the determination of applied power levels fur which nucleation is likely to occur only within the vapor grooves of the evaporator while maintaining subcooling in the liquid core, thereby increasing the likelihood of a successful startup. Also, limits are fecund for which additional increases in the applied heat flux do not increase the temperature difference between the vapor grooves and the wick-liquid core interface. This analysis is appropriate for the microscale evaporators of micro-cooler during a fully-flooded startup as well as starter pump designs and micro-CPLs(capillary pumped loops). The results are useful in the initial basic design of microscale heat transfer devices.

• Proceedings of the KWS Conference
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• 2004.05a
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• pp.48-50
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• 2004

TLP 접합 공정에서 모재와 삽입금속 사이에서의 확산을 통하여 액상 삽입금속은 고온에서 등온으로 유지 시 등온 응고된다. D.S.Duvall은 느린 가열시 매우 빠른 속도로 가열 시 보다 낮은 온도에서 dissolution이 완료되고 응고가 발생할 것으로 예상하였다. (중략)

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2000.11a
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• pp.50-54
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• 2000

The partical-image-velocimetry with liquid crystal tracers is used for visualizing and analysis of the bubbly flow in a vertical temperature gradient. This method allows simultaneous measurement of velocity and temperature flow fields at a given instant of time. Quantitative data of velocity were obtained by applying the MQD technique to visualized image. The paper describes the method, and presents the transient velocity patterns of bubbly flow.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.201-203
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• 2003

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.155-157
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• 2005

• Journal of the Korean Chemical Society
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• v.14 no.1
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• pp.109-112
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• 1970

액체구조의 천이상태 이론을 알칼리토금속 염화물에 적용시켜서 상태합을 유도하였다. 이 상태합으로부터 $SrCl_2$와 $BaCl_2$의 증기압, 몰부피, 엔트로피등의 열역학적 성질을 계산하여 실험치와 비교하였으며, 천이상태 이론이 용융염에도 잘 적용된다는 결론을 얻었다.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.70-72
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• 1989

The laser magnetic resonance (LMR) which makes use of paramagnetic properties of transient species is a powerful technique for the study of molecular radical ions. A liquid nitrogen cooled cw CO laser is developed for the LMR spectrometer in the mid-infrared region of the spectrum. The laser mid-infrared region of the spectrum. The laser system is designed to allow broad-band operation from 5 to 8${\mu}{\textrm}{m}$. The design details will be presented.

• Bulletin of the Korean Chemical Society
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• v.5 no.6
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• pp.245-248
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• 1984

Raman spectroscopy was used to study the reorientational motion of hexafluorobenzene in benzene and also in neutral solvents. From the viscosity dependence of the reorientation time, intermolecular interaction in the systems was investigated. No evidence was found to support the presence of long-lived 1:1 complex of hexafluorobenzene and benzene. The unusual viscosity dependence of the reorientational motion observed in the systems was explained as due to the formation of transient complexes.

• Journal of ILASS-Korea
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• v.15 no.2
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• pp.74-82
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• 2010

In order to understand the behavior of transient gaseous injection used in an LPG (Liquefied Petroleum Gas) engine, turbulent incompressible transient jets with butane and propane were measured and analyzed at pressures of 1.5 bar and 2.0 bar with injector diameters of 3 mm and 5 mm. Mie-scattering method with a tracer was used, and images were processed to investigate the behavior of butane and propane jets. Distances from the nozzle to transition region were measured as $L_e/d_{inj}$=4.35~19.4, where $L_e$ and $d_{inj}$ indicate respectively a distance from nozzle to transition point and nozzle diameter. Slits and tubes around jet at near-field were introduced to measure the effect of entrainment and the diameter of jet, which revealed that the entrainment of surrounding air is significant for developing jet diameter. When the entrainment is restricted, the behavior of jet became deviating from the baseline. It was found that the virtual origin located outside of a nozzle towards jet tip within the conditions of this work, and its location was estimated as $x_o/d_{inj}$=0.56~7.25, where $x_o$ is a distance from nozzle to virtual origin.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.201-207
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• 2001

We modeled the liquid film dryout(LFD) process for both tube and annulus which have uniformly heated vertical channels. We set phenomenological initial conditions in the model. The initial void fraction on the onset of the annular flow location is derived from the physical chum-to-annular flow criterion with the help of the drift-flux-model. The initial thermodynamic-equilibrium-quality is calculated by iteration with the flow quality to find the onset of the annular-flow location. Present model tends to predict very well at the lower exit quality but under-estimates at the higher exit quality. We found that the prediction error of the present model is gradually bigger as the inlet subcooling approaches near the saturation. We obtained excellent results for both tube and annulus channels as the mean of 0.97 and root-mean-square error of 11% for the number of 3883 experimental data on tubes, and of 0.96 and of 12% for 593 on annuli. The present model extended the applicable range to the relatively low exit quality region than previous LFD models.