• 유체기계공업학회:학술대회논문집
• /
• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
• /
• pp.345-350
• /
• 2000

The heat produced by the fission in the fuel of HANARO, 30 MW research reactor, is transferred from the primary cooling water to the secondary cooling water through heat exchangers, and the heat absorbed by the secondary cooling water is released into the atmosphere by the 33 MW cooling tower which is a mechanical induced draft and counter flow type. If the outlet temperature of cooling tower exceeds 33 of due to the loss of the cooling tower performance under reactor operation above $50\%$ of the full power, the reactor power should be reduced to half of the full power for safe operation. Therefore, the cooling capability of cooling tower should be maintained for the reactor to be normally operated. To predict the capability of cooling tower for full power reactor operation of 30 MW, the performance test of cooling tower was done at the reactor present power of 24 MW and the capability was respectively evaluated by characteristics and performance curves methods in accordance with the Code of Cooling Tower Institute of U.S.A. to confirm the reliability of evaluation. As a result, it was confirmed, through the results of each evaluation, that the cooling capability of cooling tower meets the design required heat load. Also, the equations of the performance and the characteristics curves of the cooling tower, based on the collected data during this performance test, was obtained for developing the calculation program to predict the cooling capability during reactor operation.

• Journal of Advanced Marine Engineering and Technology
• /
• 제28권7호
• /
• pp.1145-1151
• /
• 2004

The experiment of thermal performance about cross flow type cooling tower was conducted in this study. Generally the ambient air condition can affect the thermal performance of cooling tower to improve or not. However it is hard to control the cooling water temperature that we want under bad air condition or during rainy season. In this paper, the effect of variables, which the ambient air have. especially wet-bulb temperature, are experimentally investigated for controlling the cooling water temperature more successfully. The result is that there is appropriate air flow rate in respective air condition to preserve the cooling performance in the cooling tower and the maximum air flow rate can't overcome the approach under bad air condition.

• 한국자동차공학회논문집
• /
• 제19권6호
• /
• pp.61-67
• /
• 2011

The cooling module needs enough space (or distance) from hood to absorb the energy from any pedestrian collision. Downsized cooling module for pedestrian protection is important to reduce the severity of pedestrian injury. When a vehicle collision happens, the downsized cooling module is required to reduce the risk of injury to the upper legs of adults and the heads of children. In this study, the performance of cooling module to cool the engine was investigated under 25% height reduction. The heat dissipation and pressure drop characteristics have been experimentally studied with the variation of coolant flow rate, air inlet velocity and A/C operation ON/OFF for the downsized cooling module. The results indicated that the cooling performance was about 94% level compared to that of the conventional cooling module. Therefore, we checked that the cooling module had good performance, and expected that the cooling module could meet the same cooling performance as conventional cooling module through optimization of components efficiency.

• 동력기계공학회지
• /
• 제10권4호
• /
• pp.11-16
• /
• 2006

This research is to verify the cooling effect of the acting surface on the rotary motor using heat pipe and conventional cooling fan. In order to show the cooling performance of the rotary motor and heat pipe with the fin-typed heat sink, the surface temperature of the motor and condenser was measured in real time. The experiments were also conducted as for not only cooling device installed with heat pipe only, but with heat pipe and conventional cooling fan simultaneously. The present experiment reveals that the cooling combination of the heat pipe and cooling fan is far superior to the conventional cooling device for the driving motor such as the fin-typed heat sink. When the driving voltage of 20V and 14V were supplied to the driving motor, the cooling performance of the rotary motor with heat pipe was 170% and 500%, respectively better than that without heat pipe on steady state condition.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2007년도 동계학술발표대회 논문집
• /
• pp.197-202
• /
• 2007

In this study, the cooling characteristics of a liquid cooler using thermoelectric module was experimentally investigated. The experiment was conducted for various inner structures of liquid cooler (4 cases), hot fluid flow rates (0.15-0.25 L/min), number of T.E module (2, 4, 6 set), and the cooling water flow rates (200-600 cc/min) for both parallel and counter flow types. Among the results, better cooling performance geometry was selected. And experiment was also carried out to examine further enhancement of cooling performance by inserting coils (pitches: 0.2, 3, 6 mm) into the hot-fluid channel. Present results showed that the short serpentine type(case2) indicated the best cooling performance. In the case of coil pitch of 3 mm, the best cooling performance was shown, more than 10% increase of the inlet and outlet temperature difference, compared with the case of the cooler without coil. Consequently, the inserted coil pitch should be properly selected to improve cooling performance.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회B
• /
• pp.2079-2084
• /
• 2007

A small-scale thermoelectric cooling system was built in an effort to enhance the performance of the refrigeration system by utilizing the water-cooled jacket which was attached on the hot side of the thermoelectric module. Considered design parameters for the water-cooled jacket included the geometry of the flow passage inside the jacket and the flow rate of cooling water. The higher flow rate of cooling water in the jacket resulted in a better performance of the refrigeration system. The introduction of geometrical complexity of the cooling water flow passage to the cooling jacket also showed significant improvement on the performance of the thermoelectric refrigeration system such as the cooling capacity and the COP of the refrigeration system.

• 동력기계공학회지
• /
• 제10권4호
• /
• pp.65-70
• /
• 2006

This study is to experimentally evaluate the cooling performance of the Bonding type and Injection type of heat sink using three different kinds of industrial Peltier module by digital LabViewTM measurement. Injection type of heat sink could be more efficient for the heat transfer than Bonding type, even with 30% more radiating surface area. In addition, the experimental results revealed that the sufficient power supplied was able to show the better cooling performance of Peltier module. In order to verify the optimal cooling performance of the cooling device, two Peltier module, HMN 6040 and HMN 1550 with Bonding and Injection type of heat sink were used. The cooling performance with injection type of heat sink was 2.11% and 6.24% better than that with bonding type of heat sink under the HMN 6040 and HMN 1550, respectively.

• 한국군사과학기술학회지
• /
• 제23권3호
• /
• pp.237-245
• /
• 2020

In this paper, I introduce Phase-Change Cooling for thermal management of high power devices that can be applied to High Power Laser and Electric Propulsion Systems which are composed of multiple distributed superheat sources. Phase-Change Cooling can be good used to efficient cooling of their heat sources. Phase-Change Cooling has extremely high efficiency of two-phase heat transport by utilizing heat of vaporization, relatively low flow rates and reduced pumps power. And I suggest TPI(Thermal Performance Index) which is a quantitative performance index of Phase-Change Cooling for thermal management. I quantify the performance of Phase-Change Cooling by introducing TPI. I present the test results of TPI's changing refrigerant, heat sink and flow rate of the Phase-Change Cooling system through the experiments and analyze these results.

• 생명과학회지
• /
• 제27권5호
• /
• pp.591-599
• /
• 2017

고온 환경에서 실시하는 운동은 지구성 운동수행력에 부정적인 영향을 미친다는 사실은 잘 알려져 있다. 이러한 관점에서 지구성 선수들의 운동수행력 향상을 위한 운동 전과 운동 중 냉각요법의 다양한 중재방법에 관한 연구들이 제시되고 있지만 스포츠 현장에서 실용적으로 적용시킬 수 있는 구체적인 방안에 관한 연구가 필요한 실정이다. 이 총론은 운동유발성 열 스트레스로부터 회복과 운동수행력 향상을 위해 냉각요법에 적용된 중재방법에 관한 연구들을 분석하여 운동 전과 운동 중 그리고 운동 후에 적용될 수 있는 중재방법들을 논의하였다. 실험실 상황에서 실시된 연구결과들은 대부분 지구성 운동수행력 향상에 긍정적인 영향을 미쳤으며, 몸통냉각과 목냉각 같은 국부 냉각요법의 중재방법과 맨톨과 얼음슬러리 섭취 등의 중재방법이 스포츠 현장에서 더 실용적인 중재방법으로 적용될 수 있다. 하지만 대부분의 연구들이 실험실 상황에서 이루어졌기 때문에 스포츠 현장에서 실질적인 경기와 훈련 중에 적용할 수 있는 효과적인 중재방법에 대한 연구가 필요한 실정이다.

• 한국전산유체공학회지
• /
• 제21권1호
• /
• pp.64-71
• /
• 2016

This research is to numerically investigate the convective cooling performance in the Disk brake. Research concentrates on the heat transfer coefficient and cooling performance which are selected with cooling local locations. Cooling performance of the Hole disk has been compared by Ventilated Disk. According to the results of heat transfer on the disk brake, activated velocity distributions more appear in the Hole disk. This is due to the fact that a number of hole units have exactly 120 on the surface of the hole disk. Therefore, velocity distributions of hole disk brake is better activated than Ventilated disk. According to the calculations of Nusselt number between surface and atmosphere in the interested cooling area, average value of cooling effect has been increased 13.5% by the hole disk at driving of speed 65 km/h situation and grown 18% by the hole disk at driving speed of 100 km/h. Due to the flow of air through the hole route, cooling performance of the hole disk was very excellent. In addition, cooling effect on edge of the bottom is better than the vicinity of center.