• Nuclear Engineering and Technology
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• v.44 no.8
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• pp.831-846
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• 2012

KAERI has developed a two-phase CFD code, CUPID, for a refined calculation of transient two-phase flows related to nuclear reactor thermal hydraulics, and its numerical models have been verified in previous studies. In this paper, the CUPID code is validated against experiments on the downcomer boiling and moderator flow in a Calandria vessel. Physical models relevant to the validation are discussed. Thereafter, multi-scale thermal hydraulic analyses using the CUPID code are introduced. At first, a component-scale calculation for the passive condensate cooling tank (PCCT) of the PASCAL experiment is linked to the CFD-scale calculation for local boiling heat transfer outside the heat exchanger tube. Next, the Rossendorf coolant mixing (ROCOM) test is analyzed by using the CUPID code, which is implicitly coupled with a system-scale code, MARS.

• Journal of the Korean Society of Visualization
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• v.13 no.3
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• pp.20-23
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• 2015

In this experiment, a heterogeneous droplet consisted of de-ionized water and olive oil was made through two 31G injection needles. The injection flow rate was $50{\mu}{\ell}/min$ and the droplet size was 2 mm. The droplet was impinged onto a sapphire plate which was heated up to $300^{\circ}C$ by a heater. Two high speed cameras were used for visualization, and the frame rate was 20,000 fps. A 150W metal halite lamp was used for illumination. The dropping height was fixed to 20 mm and the corresponding Weber number was 10.6 based on water. Due to different boiling points of two liquids, partial boiling features of heterogeneous droplet was observed. At the Leidenfrost condition, micro explosion phenomenon has occurred.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.574-579
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• 1995

Saturated boiling heat transfer experiment in a hemispherical narrow space is conducted using Freon-113 to investigate an additional heat removal capability through a hypothetical gap between lower head and degraded core. The narrow space of 1mm consists of a 124mm diameter heated stainless steel hemisphere and a glass outer vessel. Within the hemispherical narrow space large coalesced bubbles are produced and these bubbles rise in random direction, causing liquid flow in from the opposite side to fill the region. Such flow in random direction makes the flow field in the narrow space very chaotic and thus enhance heat transfer. The heat transfer coefficient is higher at lower angle and at higher heat flux. The present study shows that the liquid from upper region can effectively penetrate into the gap and augment the heat removal capability through tile gap.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.679-686
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• 1999

This study is to investigate the effect of a substantial drag reduction caused by the polymer(A611P) when the working fluids flow to the vertical direction in the vertical cylindrical equipment of closed flow system. The drag reduction is associated with the mechanical degrada-tion thermal degradation and heat transfer. By ignore the heat fluxs within the closed system the pressure drop due to the polymer concentration the flow velocity and flow time have been mea-sured. By taking into account the mechanical and thermal degradation in the closed system an experiment has been focused on the determination of the condition which could improve the pump capacity in the heat union electric power plant. Under the condition of non-boiling it has been found out that the change of heat flux has little influence on the drag reduction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.3 no.1
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• pp.13-16
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• 1974

The change in color of vegetables containing chlorophyll on cooking has been of concern to food scientists. This experiment was initiated to determine the effect of different heating methods and time on the chlorophyll of green pepper. Peppers were heated at 100 C for 5, 10, and 15 min by using boiling water, steam and hot air and for 1, 2 and 3 min in microwave oven. The results showed that chlorophyll content decreased with increasing heating time. Among the heat treatments employed steaming gave the greatest effect and boiling water was the next. Hot air and microwave treated samples changed only small amount of chlorophyll. Generally pheophytin formation was increased with decreasing chlorophyll content.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.5
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• pp.12-23
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• 1994

The two-phase flow is observed in power plants, chemical process plants, and refrigeration systems etc., and it is very important to solve the heat transfer mechanism of a boiler, an automic reactor, a condenser and various types of evaporators. Recently, the problem of two phase heat transfer is braught up in many regions with development of energy saving technique. In flow boiling system it is necessary to store data in each condition because the heat transfer characteristics of flow boiling region vary by the change of flow pattern and the magnetude of heat flux to tube length, and be subtly affected by the flow and heating condition. So basic study for knowing flow pattern in heat transfer region and the relation between heat transfer characteristic and flow condition is desired to accumulate data in wide variety of liquid and flow system in the study of heat transfer of two phase flow. In this study R-113 was selected as working fluid whose properties were programmed by least square method, and experiment was conducted in the region of mass flow $1.628{\times}10^6$~$4.884{\times}10^6$/kg/$m^2$hr with inlet subcooling 10~3$0^{\circ}C$, sustaining test section inlet pressure to 1.5kg$_f$/$cm^2$abs.

• Korean Journal of Oriental Medicine
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• v.5 no.1
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• pp.59-72
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• 1999

Vibrio are become prevailing if superficial temperature of ocean is raised and their activities of area are expanded and most of ocean creatures(fishes, oysters etc) are polluted with vibrio. The one who has taken these poluted fishes and aysters uncooked caused foodpoisoning and diarrhea from Vibrio. Frequencies of these diseases breakout is disposed in westsea shore of Korea. According to ancient and traditional Korean medical book -${\ulcorner}$Bangyak Happyeon${\lrcorner}$(Collection of Local Medicines, 1884) - and their single prescribes, we carried out experiment check the activities of natural medicinal effects on Vibrio parahemolyticus. The prescriptions of trial materials are processed from extraction boiling water and 80% methanol and followed freeze dried and adsorbed to every discs in dosage of 10mg. Gentamycin of 10mg were used for control. The result of compound prescription displayed special diseases in antimicrobial activities of boiling water and MeOH extraction compared with control. In compound prescription, extraction MeOH of Sashinhwan(clear zone : 17mm) presented extraordinaire antimicrobial activity. In single prescription, extraction of boiling water(clear zone : 16mm) and MeOH(clear zone : 18mm) of Fructus Chebulae presented extraordinaire antimicrobial activity. The MBC of Fructus Chebulae extracts was expressed in boiling water(1.28mg/ml) and MeOH(0.64mg/ml).

• Journal of Sericultural and Entomological Science
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• v.31 no.1
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• pp.20-24
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• 1989

The purpose of this experiment was to obtain the basic information on heterosis and inbreeding depression of quantitative characters in the silkworm by diallel crosses of seven varieties differing widely in each character. Period of 5th instar cocoon weight, cocoon layer weight, cocoon layer ratio, boiling off ratio, raw silk percent, bave length, bave weight, bave size, weight of first molting larva and fourth molting larva were investigated. The results obtained were summarized as follows : The degrees of positive heterosis of cocoon weight and cocoon layer weight were higher. Period of 5th instar and boiling off ratio were negative heterosis. In F1 generation, cocoon weight and bave weight showed positive heterobeltiosis, while fifth instar-period, cocoon layer ratio and boiling off ratio showed negative heterobeltiosis in the F1 and F2 generation. Inbreeding depression was observed in cocoon layer ratio and boiling off ratio.

• Medical Lasers
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• v.9 no.1
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• pp.51-57
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• 2020

Background and Objectives For experiments on simulated burn, the preparation of an animal model is a very important step. The purpose of the current experiment is to design a simple and controllable method for the preparation of third-degree scald in a mouse model using the boiling water method. Materials and Methods A total of 18 Swiss mice were used. After the anesthetization, the mice were scalded by boiling water (100℃) using a mold with a 1 cm² circle area on the dorsum at contact times of 3s, 5s, and 8s. After confirming that 8 seconds of scald can cause a third-degree scald, the skin samples were collected at day 2, 4, 6, 8, 10, and 12, and analyzed by histopathological examinations. The wound retraction index (WRI) was also measured. Results Third-degree scald involving full-thickness skin was observed in the 8-second scald group, while a 3-second scald caused a superficial second-degree scald and a 5-second scald caused a deep second-degree scald. After third-degree scald, the burn wound continued to contract until day 14. Conclusion The scalding model of mice can be successfully established by the boiling water method. This method is easy to operate, it has a low cost, and it can control the scald depth by controlling the scald time. This is adequate to study skin thermal injury in the future. The scald model established by this method can last for 14 days.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.1
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• pp.8-12
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• 2014

Reduced pressure evaporation applies the principle of lowering water's boiling point by reducing the pressure. It uses the relation between temperature and pressure to reduce energy consumption needed for elevating temperature. As the result, the highest evaporation was observed at $80^{\circ}C$ and -40 cmHg applying saturated vapor pressure depending on different seawater temperature. It was found that the higher concentration in the factor test experiment depending on seawater concentration induced the higher evaporation. Also, in the factor test experiment, the amount of evaporation increased as the pressure decreased. It is concluded that the most important factor of evaporation was concentration, the second important factor was temperature, and the least important factor was pressure. Through this experiment, optimized conditions of desalination with reduced pressure evaporation device were verified.