• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.880-887
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• 1998

In order to study heat transfer characteristics of spray cooling for the purpose of uniform and soft cooling of high temperature surface a series of experiments for a hot horizontal copper flat plate was performed by downflow spray water using flat spray nozzle. Cooling curves were mea-sured under the various experimental conditions of flow rates and temperatures of cooling water Surface temperature surface heat fluxes and heat transfer coefficients of horizontal upward-facing flat surface were calculated with cooling curves measured at each radial positions near the cooling surface by TDMA method. Generally heat transfer characteristics for spray cooling is simi-lar to boiling phenomenon of pool boiling. The minimum heat flux(MHF) appear at the surface temperature of about ${\Delta}Tsat=250^{\circ}C$ and the critical heat flux(CHF) appear at about ${\Delta}Tsat=250^{\circ}C$.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.231-235
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• 1999

Cooling characteristics of cooling jacket for spindle system with built-in motor are studied. for the analysis, three dimensional model for the cooling jacket is built by using finite volume method. The three dimensional model includes the estimation on the amount of heat generation of bearing and built-in motor and the thermal characteristic values such as heat transfer coefficients on the boundary. The temperature distributions and the cooling characteristics are analyzed by using the commercial software FLUENT. Numerical results show that stream-wise cross section area and flow rate are important factors for cooling characteristics of cooling jacket. Cooling performance of cooling jacket is good in condition that stream-wise cross section's horizontal length is close to its vertical one and flow rate is high. This results show that heat transfer is dominated by velocity profile and heat transfer area.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.643-649
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• 2008

The purpose of this study is to establish a standard for unit cooling load in central control type apartment applied district cooling. The model of unit household was selected. And the standard of coefficient of overall heat transmission, location of unit household, indoor air temperature, solar radiation & thermal conduction at window and interior load was selected, and region, expansion or non-expansion of balcony, pyeong type, azimuth, rate of window area was applied as parameter. And then cooling load simulation was performed. Based on the result of simulation, the synthetic district cooling load was presented for selecting heat source of apartment applied district cooling, and unit cooling load was analyzed according to design parameter.

• 한국유체기계학회 논문집
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• 제12권2호
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• pp.24-30
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• 2009

Flow and noise analyses are conducted for examining a new design concept of impinging jet electronics cooling, and the analysis results are compared with conventional electronics cooling techniques. For the application of impinging jet electronics cooling method, the present study considers the air duct where air is supplied by axial fan and air flow from the duct is impinged vertically onto the electronic component heat source. Applying CFD simulation technique and fan noise model to the present cooling scheme, the cooling performance of the impinging jet as well as the operation condition and the noise characteristics of fan are investigated for various impinging jet nozzle conditions and fan models. Furthermore, the impinging jet electronics cooling analysis results are compared with the conventional parallel-flow cooling scheme to give the design concept and criteria of impinging jet cooling method.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.100-103
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• 2018

Due to the plasma applied from the outside, which acts as an etchant during the etching process, considerable heat is transferred to the wafer and a separate cooling process is performed to effectively remove the heat after the process. In this case, a direct cooling method using a refrigerant is suitable for cooling through effective heat exchange. The direct cooling method using the refrigerant using the latent heat exchange is superior to the cooling method using the sensible heat exchange. Therefore, in this paper, AMESim is used to design a direct refrigerant cooling system using latent heat exchange simulator was built.The constructed simulator is reliable compared with the actual experimental results. It is expected that this simulator will help to design and search for optimal process conditions.

• 반도체디스플레이기술학회지
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• 제17권4호
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• pp.51-55
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• 2018

As the OLED industry develops, display equipment is becoming larger. As a result, the stage required for display equipment is getting bigger. This enlargement led to increase in OLED production and industrial development. However, due to the large scale of the stage, other problems due to overheating and overheating caused by heavy load on the linear motor, which is mainly used in the stage, must be solved. In this study, a linear motor equipped with a cooling channel is modeled and the three - dimensional heat conduction flow analysis for this model is simulated using Fluent to analyze the cooling efficiency and cooling efficiency according to the cooling water flow rate. As a result, the cooling channel was effective and the cooling effect and efficiency were the best when the flow rate was about 5 ~ 10 L./min. In addition, the cooling effect is increased when the flow rate is increased, but the efficiency is significantly lowered when the flow rate is more than the predetermined value.

• 한국환경농학회지
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• 제15권2호
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• pp.223-231
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• 1996

폐광으로부터 유출되는 냉기 또는 냉수를 이용하여 여름 동안 야간에 온실을 냉방시키는데 있어 가장 효율적인 냉각방법을 결정하기 위해 여러 종류의 냉각 장치가 제작 및 냉각 실험되어졌다. 온실을 냉방시키는데 있어 여러 냉각장치의 효율을 비교할 때 독립적으로 소형 radiator, 냉각 pad 및 냉기를 사용한 냉각방법은 거의 비슷한 결과를 나타냈다. 또한 대형 radiator를 제외한 여러 냉각장치를 동시에 가동하였을 때는 독립적으로 이러한 냉각장치를 각각 가동하였을 때 보다 약간 향상된 냉각 효율을 나타냈다. 그러나 대형 radiator를 독립적으로 사용했을 때 온실의 냉각 효율은 다른 냉각 방법에 비하여 상당히 좋았으며, 야간의 외기 온도가 $23-24^{\circ}C$ 범위에 있을 때 온실내의 공기 온도는 약 $15^{\circ}C$로 냉각되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제35권3호
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• pp.329-334
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• 2011

The cooling water circulation plates had been used to drop the temperature of refractory outside shell of common cooling system by using cooling plate or stave type. When they are attacked by surrounding gas, they are corroded and the water flows in the refractory due to leakage of water. So, the life of refractory material is shortened and changed due to the worse conditions of cooling system. The automatic sensing device for water leakage of cooling plate is developed to check the position of trouble by using the microprocessor system when cooling water leak and gas are flowed into the cooling plate through the leakage position. The flowed gas is detected in the micro-process system which delivers the detected position of cooling plate or stave to main control room through the wireless-radio relay station. This system can be possible to detect the position of cooling plate or stave against the water leakage part immediately and then deliver the signal to main control room by using the microprocessor system and wireless-radio relay station. This system will be developed in changing the working condition from manual system to unmanned auto alarm system.

• 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.

• 한국유체기계학회 논문집
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• 제17권6호
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• pp.84-88
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• 2014

A long term passive cooling system is considered as the most important safety feature for the nuclear design after the Fukushima Daiichi nuclear power plant accident in 2011. The conventional active pump driven safety systems are not available during a station Black Out (SBO) accident. The current design requirement on cooling time of the Passive Auxiliarly Feedwater System (PAFS) is about 8 hours only. To meet the 72 hours cooling time, the pool capacity of cooling water tank should be increased as much as 3~4 times larger than that of current water cooling tank. In order to extend the cooling time for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility of the combined passive air-water cooling system. The current pool capacity of water cooling system is preserved, and the cooling capability is extended by an additional air cooler.