• 한국태양에너지학회 논문집
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• 제24권1호
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• pp.47-52
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• 2004

An experimental investigation was performed to compare ice making characteristics of ice storage system with smooth and spiral tube. During the freezing processes in the shell and tube type ice storage tank with smooth tube, heat resistance of the ice layer caused a decrease in freezing rate. Also, the phenomena of bridging made the increasing rate of ice making less. In order to improve the ice making rate, spiral tube(pitch=6mm) was used in the present study. The ice making rate and the decreasing of bridging for the spiral tube were higher than those for the smooth tube.

• Journal of Ship and Ocean Technology
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• 제8권2호
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• pp.29-40
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• 2004

Interaction of grounded ice ridges with underlying seabed is one of the major considerations in the design of Arctic pipeline system. Previously several ice scour models were developed by researchers to describe the ice scour-seabed interaction mechanism. In this paper, a parametric study on ice scouring mechanism is performed and the limitation of ice scour-seabed interaction models is discussed. Simple laboratory tests are carried out and then the shape pattern of deposited soil around the ice is redefined. New ice scour model assumes trapezoidal cross section based on the field observation data. Ice scour depth and soil resistance forces on seabed are calculated with varying the keel angle of a model ice ridge.

• 한국지구과학회지
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• 제28권5호
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• pp.598-602
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• 2007

A long-term in situ observation was carried out in the Ice-valley at Milyang in order to explain the factors and processes associated with the summertime ice formation. The variation of temperature inside Ice-valley in relation with ice formation in summer time was found to depend on precipitation rate in spring and cold air sinking in autumn and winter. The rate of temperature rising tends to correspond to sensible heat release depending on the precipitation amount at the freezing location. The reason of the cold air accumulation in a talus in the Ice-valley is the cold air sinking over the surface of talus due to the occurrence of outside clod air mass and the accumulated cold air from autumn to spring flow outside at the bottom of talus. The out-flowing cold air can result in the ice formation in the hot summer.

• 한국해양공학회지
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• 제10권2호
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• pp.20-27
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• 1996

Ice loads can determined by many factors like ice properies and dimension, velocity and type of structures. The magnitude of ice load varies with the failure mode which can be predicted by failure maps if the aspect ratio and strain rate are known. To reduce the ice force, various types of structure have been investigated and it is now known that the identor shape plays an important role in reducing ice load on Arctic offshoe structures. The conical and wedge structures are good applied examples in the Arctic region. In this study, ice forces on single wedge indentors are investigated for crushing failure mode. The ice loads on wedged indentors are compared with those on cylindrical structures. Also the concept of "ice annual"is introduced to verify the ice loads to multi and single wedge structures.tructures.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.240-247
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• 2002

Recently, a thermal energy storage system has been developed actively fur the purpose of saving energy and reducing the peak electrical demand. Especially, ice slurry is a promising working fluid for low temperature energy storage systems. A flow of ice crystals has a large cooling capacity as a result of the involvement of latent heat. However, there are still problems related to the recrystallization of ice crystals for realizing long term storage and long distance transportation. To find improvements fur this, a method for the creation of ice crystals resistant to recrystallization has been proposed and researched by the use of an antifreeze protein (AFP) solution etc. In the present study, it has been investigated the growth of ice crystal in several kinds of water solution added non-ionic surfactant. The results shows that size of ice crystal was smaller with increasing in added surfactant. And ice crystal was not increased with added surfactant.

• International Journal of Ocean System Engineering
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• 제1권1호
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• pp.32-36
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• 2011

EG/AD/S type model ice was originally selected as the primary model ice material for the MOERI ice tank in Korea. The existence of a sugar component in the EG/AD/S mixture may cause a serious maintenance problem. In order to understand the influence of sugar in the original model ice, a series of tests with EG/AD/S and EG/AD model ices were performed, and their material properties compared. Because the target strength of model ice in the full-scale MOERI ice tank is expensive and difficult to control, tests were performed under cold room conditions using a miniature ice tank. This paper describes the material properties of EG/AD/S and EG/AD model ices, such as flexural strength, compressive strength and elastic modulus. In order to obtain the desired strength and stiffness levels for the model ice, a warm-up process was introduced.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권3호
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• pp.626-639
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• 2015

Ice resistance is defined as the time average of all longitudinal forces due to ice acting on the ship. Estimation of ship's resistance in ice-covered waters is very important to both designers and shipbuilders since it is closely related to propulsion of a ship and it determines the engine power of the ship. Good ice performance requires ice resistance should be as low as possible to allow different manoeuvres. In this paper, different numerical methods are presented to calculate ice resistance, including semi-analytical method and empirical methods. A model test of an icebreaking vessel that was done in an ice basin has been introduced for going straight ahead in level ice at low speed. Then the comparison between model test results and numerical results are made. Some discussions and suggestions are presented as well to provide an insight into icebreaking vessel design at early stage.

• 한국산학기술학회논문지
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• 제21권3호
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• pp.65-72
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• 2020

얼음을 제공하는 기능이 구비된 냉장고는 대부분 냉장고 내부의 얼음 저장소에 미리 얼음을 채워 두고 사용자가 필요할 때 많은 양의 얼음을 취출할 수 있도록 하고 있다. 그러나 냉장고의 얼음 저장소에 얼음이 채워진 상태로 냉장고가 장기간 사용되지 않거나 정상적인 동작 중에도 시간이 경과하면 얼음이 서로 엉기는 현상이 발생한다. 이렇게 엉긴 얼음 덩어리를 분리시키는 메커니즘이 구비되어 있으나 얼음 엉김 현상이 심할 경우 얼음이 완전히 취출되지 못하는 문제가 있다. 본 연구에서는 이러한 문제를 해결하기 위해 얼음이 엉기는 과정과 얼음의 분리력에 관한 기존의 연구를 조사하였고, 인위적으로 얼음을 엉기게 하여 다양한 조건에서 얼음의 취출 정도를 실험하였다. 이 과정에서 얼음의 취출을 방해하는 기존 얼음 저장소 형상의 문제점에 착안하여 이를 개선하기 위한 형상과, 완전 취출을 위해 얼음 분쇄 메커니즘의 작동 반경을 넓히는 새로운 메커니즘을 제안하였다. 제안된 메커니즘의 시제품을 제작하고 실제 냉장고에 적용하여 얼음이 완전 취출됨을 검증하였다. 그 결과 기존 얼음 저장소의 형상과 분쇄 메커니즘에서 얼음 취출률이 65%정도이었으나, 제안된 형상과 메커니즘에서는 완전히 추출되었다.

• 대한조선학회논문집
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• 제49권6호
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• pp.478-483
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• 2012

The speed performances of ice sea trial on the Arctic(2010 & 2011) area were shown different results depend on the ice floe size. Penetration phenomena of level ice was not happened on medium ice floe and tore up by the impact force because the mass of medium ice floe is similar to the mass of Araon which is Korean ice breaking research vessel and did not shut up by the ice ridge or iceberg. The sea trial on the Amundsen sea was performed at the big floe which is classified by WMO(World Meteorological Organization). Three measurements of ice properties and five results of speed trial were obtained with different ice thicknesses and engine powers. To evaluate speed of level ice trial and model test results at the same ice thickness and engine power, the correction method of HSVA(Hamburg Ship Model Basin) was used. The thickness, snow effect, flexural strength and friction coefficient were corrected to compare the speed of sea trial. The analyzed speed at 1.03m thickness of big floe was 5.85 knots at 10MW power and it's 6.10 knots at 1.0m ice thickness and the same power. It's bigger than the results of level ice because big floe was also slightly tore up by the impact force of vessel based on the observation of recorded video.

• 기본간호학회지
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• 제1권1호
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• pp.37-49
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• 1994

The purpose of this study was to measure the oral temperature, skin temperature, and subjective discomfort according to the application time of ice bag on thigh, head, and abdomen. This study was also intended to suggest nursing principles about ice bag application by exploring the recovery time of skin temperature after the removal of ice bag. The design of this study was $8{\times}3$ factorial design with one sample repeated measure. Here, the application time of ice bag(criteria, 5min, 10min, 20min, 30min, 40min, 50min, 60min) and the application site of ice bag(thigh, head, abdomen) were independent variables. The subjects were 10 university woman students, and data collection was made from July, 1 to August 30, 1992. Rubber ice bag halfly filled with ice was covered with towel and applied on thigh, head and abdomen in other three days. Before applying the ice bag, oral temperature and skin temperature were checked for criteria. After ice bag was applied, skin temperature, oral temperature and VAS score were checked at first 5 minutes elapsed, and every 10 minutes until 60 minutes. After that, ice bag was removed, and oral temperature and skin temperature were also measured every ten minutes until 60 minutes. In this study, skin temperature and core temperature were measured by thermistor probe, and subjective discomfort was measured by 200mm VAS (Visual Analogue Scale). Some of the findings were as follows : 1. There were significant differences in skin temperature among the three application sites of ice bag as time go by. It was most decreased to $15.87^{\circ}C$ in thigh, and $19.47^{\circ}C$ in abdomen at 50 minutes after the application of ice bag, whereas $26.1^{\circ}C$ at 40 minutes in head. Before the application of ice bag, skin temperature showed significant differences in three sites, so that they were compared after the criteria was covariated. In other words, there was significantly more decrease of skin temperature in thigh and abdomen than head, after ice bag was applied for 20 minutes and more. 2. There was no significant difference in core temperature among the three application sites of ice bag during the time of application 3. There was no significant difference in subjective discomfort (VAS) among the three application sites of ice bag. 4. After the removal of ice bag, the recovery of skin temperature was significantly different in three sites during first 30 minutes. In head, skin temperature came up to criteria at 30 minutes after the removal of ice bag, but it was not recovered In thigh and abdomen even 60 minutes elapsed. 5. After the removal of ice bag, there was no significant difference in oral temperature among the three application sites of ice bag. 6. There was significant correlation between the skin temperature and VAS score only in thigh. In conclusion, it is suggested that head in more suitable site for the application of ice bag if it is used for the relief of fever or pain. When we apply ice bag on thigh or abdomen for the relief of pain, careful attention is required.