• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.592-598
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• 2008

Deep sea water is found more than 200 m under the surface. As no sunlight reaches, no photosynthesis takes place, and it has very little organic matter or bacteria. In addition, deep sea water maintains a consistently low temperature throughout the year, and it does not mix with the water found closer to the surface, which means that its cleanliness is preserved. It is a long-term mature sea water resource that is rich in minerals. This paper examined the physical characteristics and the uses of deep sea water, a subject that has been attracting a great deal of public attention recently, together with the current status of domestic research into it and the direction of research in the USA and Japan, focusing on the existing literature. The aim of this paper was to provide are source to researchers in the field. Since the 1970s, scientists around the world have recognized the importance of deep sea water, and have been conducting research into it. In the USA, deep sea water has been researched with the view of its application to cooling, alternative energy, farming, and the development of new materials. In Japan, about 10 local self-governing bodies are currently promoting research and business relating to deep sea water, which has resulted in a number of products that have been released to the market. In Korea, the ministry of land transport and marine affairs has been studying deep sea water since 2000, and full-scale national R&D projects have been performed by 24 organizations, including KORDI, through industrial/academic cooperation. Large companies are participating in deep sea water research projects in several ways. A study of data foundusing NDSL relating to domestic studies of deep sea water found 50 theses, 177 domestic patents, 6 analyses, 2 reports, and 2 etc. in other areas.

• Corrosion Science and Technology
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• v.10 no.6
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• pp.218-224
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• 2011

The fresh water and sea water in present ships is used as cooling water for marine engine. Therefore, corrosion damage in seawater system is frequently occurred. In particular, in the impeller of pump, the performance and material span due to the corrosion and cavitation erosion has adverse effects. Most of the pump impellers in vessels are used Cu-Al alloy. Cu-Al alloy which having the excellent mechanical properties and corrosion resistance is widely used in marine environments. However, despite the excellent characteristics, the periodic replacement parts due to the cavitation damage in seawater is vulnerable to economic viewpoint. In this study, Cu-Al alloy used with impeller for centrifugal pump were conducted various experiments to evaluate its characteristics in seawater and fresh water solutions. As an electrochemical result, the dynamic conditions that exposed to the cavitation environment presented high corrosion current density with collapse of the cavity compared with the static conditions. Cavitation test results, the weightloss and weightloss rate in fresh water are observed more than those of seawater.

• Proceedings of the KWS Conference
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• 2004.05a
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• pp.203-205
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• 2004

Welding sometimes should be done inside-hull after launching. The opposite side is contacted sea-water In this case, it should be a concern that the cooling rate expected very rapid may deteriorate microstructures, and hence these microstructures are hardened, cracking happens, or toughness would be impaired. Therefore, a test program simulating the situation has been planned and welded using the ship class materials (AH32, EH36) with the related welding consumables (E71Tl-1, E81Tl-K2) and then carried out to investigate the effect of cooling rate on weldments quality. Based on the test results, it could be concluded that the welds of which the opposite side of arc is exposed to wet or flowing water are not affected by rapid cooling.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.2
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• pp.102-107
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• 2007

A remarkable sea surface cooling (SSC) event was observed in the eastern sea of Korean peninsula based on new generation sea surface temperature (NGSST) satellite images in September 2005, when typhoon Nabi passed over the East Sea. The degree of SSC ranged from $1^{\circ}C\;to\;4^{\circ}C$, and its maximum was observed in the southeastern sea area. Daily variations in sea surface temperature at a longitudinal line $(35^{\circ}-41^{\circ}N,\;132^{\circ}E)$, derived from satellite data for September 1-13, 2005, showed that the SSC lasted about 3 days after the typhoon passed in the south of $39^{\circ}N$, whereas it was unclear in the north of$39^{\circ}N$. Water temperature measured by a mooring buoy suggested that the SSC was caused mainly by a vertical mixing of the water column driven by the typhoon, rather than by coastal upwelling.

• 한국수산학회:학술대회논문집
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• 2005.05a
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• pp.161-161
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• 2005

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.5
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• pp.595-602
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• 2012

In this study, for the purpose of reduction of $CO_2$ gas emission and to increase recovery of waste heat from ships, the ORC (Organic Rankine Cycle) is investigated and offered for the conversion of temperature heat to electricity from waste heat energy from ships. Simulation was performed with waste heat from the exhaust gasse which is relatively high temperature and cooling sea water which is relatively low temperature from ships. Various fluid is used for simulation of the ORC system with variable temperature and flow condition and efficiency of system and output power is compared. Finally, 2,400kW output power is obtained by system optimization of the preheater and reheater utilizing waste heat form sea water cooling system.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.2
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• pp.196-200
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• 1999

In the case that erosion and corrosion occurs in machinery and structure at the same time, the synergy effect by erosion-corrosion affects fatal effect to durability of machinery and structure. Therefore, in machinery and structure which use corrosion liquid, the study of the synergy effect of erosion-corrosion which affects metal material is requested. In this paper. the flow corrosion experiment about the effect of temperature change and liquid velocity change in sea water was carried out to study the characteristics of erosion-corrosion for tube material Cu heat exchanger The main results obtained are as follows. (1) Damage appearance of tube outside by erosion-corrosion becomes dull because electrode potentials of Cu tube is higher than electrode potential of STPG38 shell. (2) In the cooling system by sea water, the weight loss rate of Cu at tube outside liquid temperature of $70^{\circ}C$ is higher than that of temperature of $20^{\circ}C$. (3) In cooling system by sea water, the weight loss rate of Cu at liquid velocity of 5.1m/s is higher than that of velocity of 1.47m/s. But as the testing time passed, the weight loss rate of Cu at velocity of 5.1m/s is almost steady and becomes dull at velocity of 1.47m/s.

• Journal of Navigation and Port Research
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• v.36 no.1
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• pp.35-41
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• 2012

In this paper, we analyze the current submarine cooling system and study control algorithms for cooling system. Cooling system are installed in the submarine propulsion motor to protect the motor from high-temperature by iron loss and copper loss. The cooling system control the sea water and fresh water pump RPM to keep the motor temperature stable by external environment and motor RPM holding time. The cooling system simulation program is made for checking the cooling performance, and simulation is performed with various control strategy. The results with proposed cooling algorithm is shown to improve the thermal stability and efficiency of cooling system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.523-528
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• 1998

To clarify the effect of life or death condition before cooling on the physicochemical properties of plaice, Paralichthys olivaceus muscle at the early period after death, the plaices were dipped in the refrigerated sea water ($0^{\circ}C$) either as alive or after anesthesia killing. These samples were stored at $0^{\circ}C$ sea water and the changes in rigor-mortis, ATP breakdown, content of ATP and its related compounds, breaking strength and lactate accumulation through storage were investigated. Acceleration of rigor-mortis, ATP breakdown and lactate accumulation were taster in the samples refrigerated as alive than in samples killed by anesthesia before cooling. ATP in samples refrigerated as alive showed little breakdown until 7.5 hrs but it was decomposed completely after 17.5 hrs storage. The breaking strength in muscle of plaice was 1736.2 $\pm$ 65.4 g immediately after killing. The breaking strength in samples dipped in refrigerated sea water as alive increased more rapidly and showed the maximum value over 7.5 hrs (2183.3$\pm$32.2 g), However, in case of samples killed by anesthesia before cooling, the value and time reached around the maximum breaking strength were 2126.3 $\pm$ 32.2 g and 12.5 hrs, respectively and then decreased until 30 hrs. From these results, it could be suggested that dipping in refrigerated sea water after anesthesia killing before cooling is more effective in maintaining freshness of fresh plaice muscle than refrigerating as alive.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.544-549
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• 2009

The purpose of this study is to investigate the field Operation Characteristics of a sea water heat source cascade heat pump system and system applicable to Building. Cascade heat pump system is composed R410A compressor, R134a compressor, EEV, cascade heat exchanger, Plate heat exchanger etc. Building area is $890m^2$ and has five floors above ground. R410A is used for a low-stage working fluid while R134a is for a high-stage. The system could runs at dual mode. One is mode of general R410A refrigeration cycle in summer and the other is cascade cycle. In order to gain a high temperature supply water in winter season, the system is designed to perform a cascade cycle. The filed test results show that the sea water heat source heat pump system exhibits a COP of about 5.5 in cooling mode along with a heating COP of about 4.0 in 1-stage heating mode. Cascade 2-stage heat pump system is enough to supply $60^{\circ}C$ water and heating COP is about 3.0