• 융합정보논문지
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• 제11권2호
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• pp.90-97
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• 2021

본 연구에서는 산업현장에서 미활용되는 열에너지를 회수하여 유용한 전기에너지로 변환하기 위한 Bi2Te3 계열 열전소자를 제작하고 에너지회수 성능 및 물성을 도출하였다. 성능시험을 위하여 카트리지 히터 가열 방식의 가열블록과 냉매가 흐르는 냉각블록으로 구성된 전용 실험장치를 구성하였으며, 가열블록과 냉각블록에는 3×3 배열의 열전대를 장착하여 소자 양 면 온도와 열전달율을 도출하였다. 최소 온도차 27K부터 최대 온도차 172.2K까지 총 9가지의 온도차에 대해 실험을 수행하여 V-I curve와 P-R curve를 도출하였고 성능에 주요한 영향을 미치는 제벡계수 등 변수 7가지에 대하여 온도차에 대한 함수로 결과를 제시하였다. 최대 발전양 7.5W와 변환효율 11.3%의 결과로부터 개발된 열전소자의 열에너지 회수 성능의 타당성을 검증하였다.

• 대한조선학회논문집
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• 제41권4호
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• pp.85-91
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• 2004

The objective of the present paper is to develop an analysis method for the correction of welding deformation of stiffened plate by line heating. In this paper, the equivalent loading method, based on the inherent strain theory, was used to analyze the heat-straightening of a stiffened plate. Equivalent loads were obtained by integrating the inherent strains which were determined from the highest temperature and the degree of restraint. Finally, the obtained equivalent loads were imposed, as applied loads, on the elastic analysis for the prediction of correction of welding deformation in stiffened plate. The proposed method is expected as a basic study in heat-straightening analysis of welding deformation in large scale block.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1406-1411
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• 2004

A series of experiments was conducted to examine characteristics of a grooved flat-strip heat pipe having multiple heat sources. The inner grooves of the heat pipe have the aspect ratio of 1 to $2.5(0.42{\times}1.05$ mm) whose pitch was 0.6 mm. Four block heaters ($10{\times}20$ mm) were placed in the evaporator section at intervals of 20 mm and six different heating modes were tested. The maximum surface heat flux of 80 $W/cm^2$ was achieved while the operating temperature was kept below $100^{\circ}C$, In the nearest heating mode (from the condenser location), the heat pipe exhibited more stable temperature distribution than the far heating mode where the heaters is located furthest from the condenser.

• Computers and Concrete
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• 제24권5호
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• pp.437-444
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• 2019

PLC and its expansion module, electric ball valve and cooling pipe, electric heating steel plate and various components of the system, which is used to control test and process data. By automatically adjusting the opening of the valve, the system makes the top temperature and cooling speed develop along the ideal temperature diachronic curve. Moreover, the system enables the temperature difference between inside and surface of test block limited in a given range by automatically controlling the surface board heating. The method of physical simulation test by sandbox with built-in cooling water pipe and heating rod is adopted. On the premise of a given standard value, the operation of the system is checked under different working conditions. Further, an extension of this system is proposed, which enables its application to obtain some thermal parameters when cooperating with numerical simulation.

• 한국결정성장학회지
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• 제19권6호
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• pp.311-317
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• 2009

CAD/CAM 가공이 가능한 치과용 3Y-TZP블록을 제조하였다. 블록 제조를 위하여 3Y-TZP분말에 $HfO_2$와 $CeO_2$ 분말을 첨가하여 $800{\sim}1100^{\circ}C$에서 열처리 한 후 $1450^{\circ}C$에서 소결하였으며, 이때 $HfO_2$와 $CeO_2$ 분말의 첨가량 및 열처리 조건에 따른 블록의 기계적 특성 및 화학적 특성을 조사하였다. EDS mapping 이미지를 통하여 $HfO_2$와 $CeO_2$ 분말이 3Y-TZP에 비교적 분산이 잘되어 있음을 확인하였다. 본 실험에서는 3 wt% $HfO_2$가 첨가된 블록이 가장 높은 굽힘 강도(1 GPa)를 나타내었으며, 3 wt% $CeO_2$가 첨가된 블록은 수열분위기하에서의 $t-ZrO_2$의 안정성을 향상 시키는 것으로 확인되었다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.324-329
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• 2008

The liquid cooling effect of a natural convection type radiator by using the PCM has been investigated experimentally. The radiator size is $423{\times}295{\times}83$ mm and PCM container size is $398{\times}270{\times}26$ mm. The objective is elapsed time higher than maximum time to reach for maximum operating temperature of a general liquid cooling radiator. This study, in order to study on the effects of the phase-change phenomenon, carried out the various mass flow rate, input electric power, ambient and melting point of three type PCM. For the above experimental parameter, the melting time was performed about 180/250/560 min at input power 150 W and ambient $30^{\circ}C$ from using the three type PCM(PCM_S1/S2/S3) respectively. Furthermore, the effects of the thermal dissipation was decreased higher input power than lower input power at heating block and melting time of PCM. However, the effects of mass flow rate did not nearly affect of the thermal performance especially.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.129.2-129.2
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• 2010

As a part of the government renewable energy policy, KOWEPO is constructing 300MW IGCC plant in Taean. IGCC plant consists of gasification block, air separation unit and power block, which performance test is separately conducted. Overall performance test for IGCC plant is peformed to comply with ASME PTC 46. Major factors affected on the overall efficiency for IGCC plant are external conditions, each block performance(gasification, ASU, power block), water/steam integration and air integration. Performance parameters of IGCC plant are cold gas efficiency, oxygen consumption, sensible heat recovery of syngas cooler for gasification block and purity of oxygen, flow amount of oxygen and nitrogen, power consumption for air separation unit and steam/water integration among the each block. The gas turbine capacity applied to the IGCC plant is 20 percent higher than NGCC gas turbine due to the low caloric heating value of syngas, therefor it is possible to utilize air integration between gas turbine and air separation unit to improve overall efficiency of the IGCC plant and there is a little impact on the ambient condition. It is very important to optimize the air integration design with consideration to the optimized integration ratio and the reliable operation. Optimized steam/water integration between power block and gasification block can improve overall efficiency of IGCC plant where the optimized heat recovery from gasification block should be considered. Finally, It is possibile to achieve the target efficiency above 42 percent(HHV, Net) for 300MW Taean IGCC plant by optimized design and integration.

• 한국건설순환자원학회논문집
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• 제10권2호
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• pp.176-183
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• 2022

저전력 사용이 가능한 발열콘크리트를 제작하기 위하여 시멘트 모르타르에 고순도 폐CNT를 혼입하였으며, 모르타르의 전도율을 향상시키기 위하여 압축강도를 제어하는 수준에서 탄소섬유와 폐음극재를 활용하고자 하였다. 사용된 폐CNT는 다중벽 CNT의 함유량이 많은 것으로 분석되었고, 모르타르 배합시 분산성을 높이기 위하여 액상형으로 치환하여 사용하였다. 모르타르 발열시 태양광 등에 의한 소형 자가발전 설비를 활용하고 전자파를 최소화하기 위하여 DC 24 V이하의 전력 사용시의 모르타르의 온도 변화를 평가하였다. 액상형 폐CNT를 적용하고, DC 24 V의 전압을 도입한 경우 200 × 100 × 50 mm 블럭 시험편에서 60 ℃까지 상승하였으며, 액상형 폐CNT와 탄소섬유, 폐음극재를 모두 사용한 경우에는 DC 12 V에서도 55 ℃이상까지 온도가 상승하여 현장 적용성이 충분한 것으로 판단되었다. 특히 발열에너지 변화량에 있어서도 다른 변수들과 비교하여 효과적인 것으로 나타났다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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• pp.311-317
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• 2008

As outdoor environment become worse due to concentration of population in large cities, the importance of environmental control strategies such as the arrangement of green space or water space and ventilation paths, has been increasingly recognized. However, most of the studies focus on the assessment on outdoor thermal environment, few studies focus on the interrelationship between thermal environment in residential block and human thermal comfort. The aims of this study is to develop the outdoor planning method to reduce the heating/cooling load in an apartment unit or entire block by the sustainable approaches in outdoor environmental design. In this paper, on the basis of the prior studies, the effect of the outdoor thermal environment on human thermal comfort will be analysed.

• 대한건축학회논문집:계획계
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• 제34권2호
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• pp.3-11
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• 2018

Korea has achieved a rapid economic development and with the increase in population and national income and the expansion of social and economic activities, energy consumption has rapidly increased too. Energy consumption per head has constantly increased and currently, power consumption per head is 7.5 times bigger than in 1985. Buildings occupy 25% of total energy consumption and especially, 50% of total energy is consumed for heating and cooling. In this situation, multi-family housing, which has constantly been increased, has an energy saving rate of 1.9%, which is the lowest level and this makes the government's energy policy for sustainable energy system development useless. Besides, energy consumption leads to secondary problems, such as air, water and marine pollution and heat pollution and wastewater/drainage and the increased use of fossil fuel is a fundamental reason for ozone layer destruction and global warming. Therefore, efficient energy consumption plans are required. This study aims to analyze energy performance in each block type of high-rise and diversified multi-family housing that accounts for 60% of all the housing forms, depending on the variations in stories through BIM-based energy simulation. For this study, four representative block types were selected, based on the multi-family floor plan, which is certified for energy performance evaluation and they were applied to the floor plan of a multi-family house that is scheduled to be built. Then BIM modeling was conducted from the fifth story to the 40th story at an intervals of 5 stories and based on the finding, energy characteristics of each block type and energy performance depending on the variations in stories were analyzed. It is considered that this would serve as objective data for block type and block story decision of energy performance-based multi-family housing.