• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.236-241
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• 2009

After analyzing the characteristics of the cooling dryer, the mixed cooling dryer was developed by adding the desiccant dryer which supplement the cooling dryer's demerits. Also, the hybrid desiccant cooling dryer was developed to use effectively the exhaust heat energy of the cooling dryer. It could make a more that 20 percent reduction in energy compared with the mixed desiccant cooling dryer. It has become essential to supply this equipment and search the suitable drying product.

• 대한기계학회논문집
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• 제16권6호
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• pp.1150-1155
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• 1992

본 연구에서는 제철소 열연공정의 냉각효율 개선을 위한 기초연구로 수행되었 다. 전열면의 초기온도가 900.deg. C이상일 때 층류 냉각방식에 의한 고온강판의 냉각특 성에 영향을 주는 모든 인자를 엄밀히 고려하는 것은 매우 어려운 일이다.따라서 본 연구에서는 노즐과 고온면 사이 거리(L), 유량(Q), 냉각 초기온도 등을 실제 작업 조건에 가깝게 변화시켜 가면서 수냉반경의 변화를 중심으로 전열면의 냉각 특성을 해 석하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.254-257
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• 2008

For crystalline slags, of which the viscosity rapidly increases at $T_{cv}$ due to the formation of crystalline phases, the Tcv is affected by measurement conditions. In this study, we investigated the effect of cooling rate, and alumina dissolution on the determination of $T_{cv}$. Using synthetic slag samples based on the composition of Alaska Usibelli slag, $T_{cv}$ were determined under a constant cooling rate of $2^{\circ}C$/min, and under rapid cooling with holding time to allow the slag to reach thermal and rheological equilibrium. The effect of alumina dissolution was investigated using platinum lined crucibles. The constant cooling resulted in lower $T_{cv}$ by $33^{\circ}C$ as compared to the equilibrium measurements. Under $2^{\circ}C$/min cooling, the blocking alumina dissolution resulted in lower $T_{cv}$ by $23^{\circ}C$. When the $T_{cv}$ was measured under $2^{\circ}C$/min cooling using an alumina crucible, therefore, the effects of a constant cooling is somewhat offset by the alumina dissolution effect, and bring the measured value closer to the true value.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2518-2523
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• 2007

In this paper, thermo-flow characteristics of an outer-rotor type of a BLDC motor are numerically analyzed using three-dimensional turbulence modeling. In an advance design of BLDC motor, cooling blades and holes are preferred for the enhanced cooling performances. Rotating the blades and holes generates axial air flow passing through stator slots, which cools down stator by forced convection. For the present study, a new design of the BLDC motor has been developed and major design parameters such as the arrangement of cooling holes, the area of cooling holes, and cooling blades and the cooling blade angle, are analyzed for the enhanced convective heat transfer rate. It is found that the convective heat transfer rate of the new BLDC motor model is increased by about 8.1%, compared to that of the reference model.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.691-696
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• 2000

Cooling characteristics of cooling jacket for spindle system with built-in motor are studied. Three dimensional model was selected for the analysis of the helical-type cooling jacket. This model includes the estimation on the amount of heat generation from bearing and built-in motor and the thermal characteristic values such as heat flux on the boundary. The temperature distributions are analyzed and the cooling by Nusselt number and total heat transfer coefficient. Numerical results show that stream-wise cross section area and flow rate are important factors for cooling characteristics of cooling jacket.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.249-256
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• 2009

The cooling technology of power conversion semiconductors in the propulsion system for the HEMU(High Electrical Multi Unit) are applied in water cooling method and phase change method such as the immersed type and the heat pipe type. This research designs and manufactures the water cooling system that could cool about heat load Q=2kW and performance tests to apply it by an electric power conversion semiconductors(IGBT) cooling technology. Experimental condition made change of a flow rate, an air velocity and a heat load to confirm operation characteristics of water cooling device, and when is heat load 2kW, air velocity 20 m/s, and water flow rate 7kg/s, it is about $80^{\circ}C$ to temperature of cooling plate.

• 에너지공학
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• 제20권4호
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• pp.259-266
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• 2011

원자로 정지냉각계통은 원자로 정지 시 핵연료 잔열 제거를 위하여 냉각수가 충분히 공급하고 원자로기기들을 보호할 수 있는 냉각율을 유지할 수 있도록 설계되어야 한다. 경수로 정지냉각계통을 분석하기 위한 KDESCENT코드를 중수로 정지냉각계통에 적용하여 보았으며 기존의 중수로형 해석코드인 SOPHT, SDCS 코드 결과와 비교분석하였다. 정지냉각펌프 모드와 열수송펌프 모드에서 정상냉각 운전상태는 계통의 설계 요건을 만족시켰으며 정지냉각 열교환기를 열제거원으로 사용하였을 때 냉각률은 설계요건에서 규정하고 있는 제한치인 $2.8^{\circ}C/min$ 이하의 값을 얻었다. 전반적인 냉각능력 분석 결과 월성 2, 3, 4호기 정지냉각계통은 핵연료로부터 핵분열 생성물의 방출을 충분히 제한하고 핵연료채널의 건전성을 유지시키기 위한 충분한 냉각을 핵연료에 제공하였다.

• 한국자동차공학회논문집
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• 제9권3호
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• pp.35-41
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• 2001

In recent applications, map controlled thermostat has been adapted to optimize engine cooling system and vehicle cooling system. First of all, this strategy is focused on improving fuel consumption rate and reducing emissions, especially unburned hydrocarbon. The object can be obtained through controlling engine metal temperature by varying engine coolant temperature with engine load and speed. To achieve this goal, it is necessary to understand the characteristics of engine metal temperature and heat rejection rate to coolant. From the results of tested engines, it is obvious that fuel consumption rate has more dominant effect on engine metal temperatures than the corresponding engine power does. Also, Re-Nu relation which shows heat rejection rate to coolant in function of air-fuel mixture and engine specifications has been studied. Also, the empirical Re-Nu relation at full loaded engine was developed.

• 대한설비공학회지:설비저널
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• 제16권3호
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• pp.295-304
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• 1987

The purpose of this study is to develop a computer model for simulating the water-lit hium bromide absorption heat transformer (AHT) Including all major components and to find the flexibility in operation. The effect of source hot water temperature, cooling water temperature, useful hot water flow rate, cooling water flow rate and evaporator circulation flow rate were investigated. The coefficient of performance (COP), temperature boost $({\Delta}T\;=\;T_A\;-\;Ti)$ and concentration variations can be predicted. The performance study indicates that the performance of AHT increases for the waste hot water temperature increasing and with a decrease of the cooling water temperature. The effect on performances of useful hot water flow rape is significant except on temperature boost. Also the effects on performance of cooling water flow rate and evaporator circulation flow rate are small. It is shown that the computer program is valuable to predict the performance of absorp-tion heat transformer units at various working corditions.

• Design & Manufacturing
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• 제6권1호
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• pp.1-4
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• 2012

Plastic products are producted more than 70% of total processes in the injection molding. The injection molding process has 4 processes such as filling, packing, cooling and ejecting. It spends most of times in the cooling process. Therefore, it is important to control the mold temperature in producing plastic products. The time and system of cooling affect the product's quality and productivity. Especially, cooling time has about 60% of total injection cycle time. Therefore, we can improve a productivity by shortening cooling time. In this study, it was made a comparative study about cooling of linear channels and baffles and observed the variation of mold temperature on the coolant's temperature. As the result, the linear channel's cooling rate had faster than baffles and as coolant's temperature was increased, difference of cooling time was increased. Result of this study will be used widely to design for cooling system of injection mold.