• 한국항공우주학회지
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• 제38권11호
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• pp.1105-1114
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• 2010

착빙현상은 크게 서리얼음과 유리얼음으로 구분되며 대기온도 뿐 아니라 자유류 속도, 대기 중 수증기 함유량, 수증기 입자의 크기는 결빙형상에 영향을 미친다. 본 논문에서는 결빙 형상에 영향을 미치는 외기조건에 의해 변화하는 결빙형상을 체계적, 정량적으로 분석하여 다음과 같은 결과 확인하였다. 먼저, 자유류 속도의 증가는 결빙면적, 얼음 진행방향, 최대 두께를 모두 증가시키고 결빙형상을 가장 크게 변화시켰다. 둘째, LWC와 결빙면적은 선형적인 관계가 있음을 알 수 있었다. 셋째, 대기온도가 수증기 유입량에 미치는 영향은 LWC, 자유류 속도에 의한 영향에 비해 적어 결빙면적의 변화가 가장 작게 나타났다. 넷째, MVD가 결빙 형상에 미치는 영향은 선정한 외기 조건 중에 가장 미미하였다. 단, 입자가 표면에 충돌하는 영역을 증가시켜 결빙면적에 영향을 주었다.

• 대한조선학회논문집
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• 제51권2호
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• pp.107-113
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• 2014

The icebreaking research vessel, ARAON had her second ice trial in the Arctic Sea from 16th July to 12th August 2010. During the voyage, the local ice loads acting on the bow of port side were measured from 14 strain gauges. The measurements were also carried out in ice waters with various ice concentration ratio as well as the icebreaking performance tests. In this study, the ice loads measured during the 'general' operation in ice waters were analyzed. As a first step, the relationship between the location of strain gauges and the ice loads were investigated, and then the possibility for observation of higher ice loads was estimated based on the probability density function. The relationship between the ship speed and the ice load was also investigated. 718 peak stresses data higher than 20 MPa obtained from strain gauges array attached in longitudinally and vertically was analyzed. In general, the ice load increases as the ship speed increases in the low ship speed range, and ice load decreases as the ship speed is greater than a certain speed.

• 동아시아식생활학회지
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• 제7권3호
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• pp.355-363
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• 1997

This study was designed to investigate development points for automatic ice maker which met consumer's demand. Basic data about using ices in Korean's dietary life, were collected from Seoul and Kyunggi-do residences and analyzed by SPSS program. The results were as follows; 93.7% of respondents had 3 major domestic brands' refrigerator and 41.4% of them had medium-large capacity(400-519L). 65% of respondents had a refrigerator that was purchased less than five years. 15.5% of respondents had one more refrigerator. Among of them, major refrigerator was located in kitchen(67.7%) and minor was in kitchen(29.8%) and in veranda or multi-purpose room(26.3%). 66.2% of respondents always prepared ices in ice container, and 85% of them used ice only in summer. Boiling water with barley or corn was used as drinking water (45.6%) and boiled or purified tap water was used to make ice (38.6%) commonly. In cooking, ice was used especially in cold soup with cucumber and seaweed(89.9%), ice-tea or ice-coffee(81%), and fruit punch(64%). The next commonly using ice was adding in alcoholic beverage such as whiskey(57.4%), in Koreans traditional drink(Misugaru) (45.2%) and juice. The purpose of using ice was to cool in soft drink (58.6%), to cool in cooking food(19.9%), to eat ice itself(14.0%), and to enjoy more fantastic taste and mood(3.8%). In whiskey, the purpose of using ices was to control alcoholic content (52.9%). There was no significant difference between sex in the purpose of using ice, but there was significant differences between age(p＜0.05). Seasonal variations in using ice, there were significant differences according to sex, age, roles in family, amount of preparation of ice, socio-economic level and brand and capacity of refrigerator in respondent's home.

• 대한조선학회논문집
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• 제43권2호
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• pp.147-155
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• 2006

Ice resistance estimation equations based on model tests and full-scale sea trial data from many previous research articles are studied. Measured ice resistance data and its empirical/semi-empirical estimation equations are summarized in common format and are compared with each other, considering three ship categories, i.e, icebreakers, tug/supply vessels, ice-strengthened cargo vessels. The most suitable estimation methods or prediction equations are recommended based on this ice resistance data analysis.

• 동력기계공학회지
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• 제16권5호
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• pp.32-39
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• 2012

The study experimented to understand ice-on-coil type ice making characteristics on to 3 kinds of circular tube, oval tube and small diameter tube using ice maker. The experiment were carried out under various conditions, that used brine temperature($-10^{\circ}C$, $-6^{\circ}C$), brine flow rate(1.0m/s, 1.8m/s) and inlet water temperature ($6^{\circ}C$, $12^{\circ}C$) etc. Mass of ice per ice making area increased according to the decrease of the brine temperature and inlet water temperature, but that was increased according to the increase of the brine flow rate. Oval ice making tube produced ice 1.11 to 2.46 times that of 9mm circular ice making tube, and 3mm small diameter ice making tube produced ice 1.06 to 1.51 times that of 9mm circular ice making tube.

• 동아시아식생활학회지
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• 제7권2호
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• pp.211-220
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• 1997

This study was investigated about preparation of ice at home and developing points which met consumer's demand that was focused on auto icemaker. According to purposive quota sampling method, residences in Seoul and Kyunggi-do area were selected and interviewed by trained interviewer at August 1995. The results were as follows: 66.3% of respondent usually prepared ice in ice-making container of refrigerator and used when they needed. 85% of them used ice in summer and seldomly used in other seasons. Boiling water with barley was major drinking water(45.6%), and broiled or purified tap water was used to make ice(38.6%) commonly. Numbers of ice-making container were two(66.0%). Above 50% of respondents replied that they felt off-flavor in ice usually. After felt off-flavor, 54.7% of respondent threw away the ice, some of them used off-flavored ice after treatment to washing with water. 64.9% of respondents thought that the origins of off-flavor was the flavor of refrigerator itself. The consumer's expectation of developing points were as follows. The most priority of developing points was to make ice quickly, the next was to develop auto ice maker and ice storage container, to make different size of ice. Less expected points were to make more clear ice and large volume of ice in one time. The recognition about auto ice maker was slightly low(35% of respondents), but 67% of them wanted to develop auto ice maker.

• 설비공학논문집
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• 제14권12호
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• pp.1063-1070
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• 2002

To resist ice adhesion on cooling wall is concerned to continuous ice formation in thermal storage system. In this study, ice slurries were formed with two ecological aqueous solution, one is ethanol+silanol and the other is propylene glycol+silanol. By freezing under stirring the solution of $300m\ell$ in a stainless steel vessel which was immersed and cooled in a temperature controlled bath, the shape of ice slurry and the strength of ice adhesion on wall was observed with measuring the temperature and stirring load variation. As the concentration is smaller and the supercooling degree is larger, the ice adhesion is easy to occur. When the stirring load is larger than$ 2.1\times10^{-5}W$, the ice adhesion occurred.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.280-280
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• 2012

We examined ammonia diffusion on the surface of amorphous ice film through the measurement of decreasing residual quantity of $NH_3$ molecules compared to $H_2O$. The populations of $NH_3$ molecules on the surface of amorphous ice were monitored by using the techniques of temperature programmed reactive ion scattering (TPRIS) method. The ratio of intensity between ammonia and water was examined as a function of time at controlled temperature. When ammonia molecules were externally added onto an ice film at a temperature of 80 K, ammonia coverage with regard to ice was 0.12-0.16 ML. The intensity of ammonia molecules on the surface of ice decreased as time increased and the extent of decreased intensity of ammonia increased as controlled temperature increased. Moreover, energy barrier was estimated to be $51kJmol^{-1}$ on amorphous ice film. The results of the experiment indicate that ammonia molecules have a property of vertical diffusion into amorphous ice and the energy barrier of ammonia diffusion into bulk of ice is higher than that of hydrogen bonding.

• 한국태양에너지학회 논문집
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• 제22권2호
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• pp.11-17
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• 2002

This paper is concerned with the development of a new method for making, separating ice and storage floated ice by installing an evaporation plate at under-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating an ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. Developed new harvest-type method shows good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, however these components are not necessary in a new method. In this study ice storage systems are experimentally investigated to study the charge and discharge of thermal energy. The results show the applicable possibility and performance enhancement of a new type.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권2호
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• pp.119-128
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• 2018

A numerical method is proposed to simulate level ice interaction with ship in transverse and longitudinal directions in time domain. A novel method is proposed to simulate non-symmetric transverse force in a stochastic way. On the basis of observations from the model tests, the simulation of longitudinal force combines the ice bending force acting on the waterline, submersion force below the waterline and ice friction forces caused by transverse force and ice floes rotation amidships. In the simulations the ship was fixed and towed through an intact ice sheet at a certain speed. The setup of the numerical simulation is similar to the ice tank setup as much as possible. The simulated results are compared with model tests data and the results show good agreement with the measurement.