http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
마이크로 캡슐 잠열재 슬러리를 적용한 미소채널 열교환기의 열분배 성능평가
전종욱(Jongug Jeon),백창현(Changhuyn Back),김용찬(Yongchan Kim),김영득(Young-Deug Km),최종민(Jong Min Choi) 대한설비공학회 2006 대한설비공학회 학술발표대회논문집 Vol.2006 No.6
The heat transfer performance and energy transport ability are relatively high due to higher specific heat. Therefore, it can be used in fields such as heating, ventilating, air-conditioning, refrigeration and heat exchangers. In this study, liquid-cooling heat exchangers were designed and tested by varying geometry and operating conditions. In addition, liquid-cooling heat exchangers were tested to provide performance data for MPCM slurry. The liquid-cooling heat exchangers had twelve rectangular channels with flow paths of 1, 2, 4 and 12. Silicon rubber heaters were used to control the heat load to the heat exchanger. Heat input ranged from 293 to 800 W, and inlet temperatures of working fluid varied from 15 to 27℃ The standard deviation of surface temperature was strongly affected by the coolant of MPCM Slurry. All MPCM-cooling heat exchangers showed higher cooling performance than the water-cooling heat exchanger except one path channel heat exchanger.
전종욱(Jongug Jeon),백창현(Changhuyn Beak),김용찬(Yongchan Kim),최종민(Jong Min Choi) 대한설비공학회 2006 대한설비공학회 학술발표대회논문집 Vol.2006 No.11
In this study, liquid cooling heat exchangers for telecommunication equipment were designed and tested by varying heat density and operating conditions. The optimal design of liquid cooling heat exchanger was discussed. The liquid-cooling heat exchangers had twelve rectangular channels with different flow paths of 1, 2, 4, and 12. Silicon rubber heaters were used to control the heat load to the heat exchangers. Heat input ranged from 293 to 800W, and inlet temperatures of working fluid varied from 15 to 27℃. The local heat transfer coefficients defined by the mean temperature of the working fluid were compared with the increase of mass flow rate. The heat transfer coefficients were strongly affected by flow conditions. The enhancement factor which was defined as the ratio of heat transfer enhancement factor to pressure drop penalty factor was employed to estimate the performance of the heat exchangers. Even though the 4 path channel heat exchanger showed higher heat transfer coefficient than the 12 path channel heat exchanger, the enhancement factor of the 12 path channel heat exchanger was higher than the 4 path channel heat exchanger due to a lower pressure drop.
전종욱(Jongug Jeon),박종삼(Jongsam Park),명우호(Wooho Myung),김용기(Young-Ki Kim),김용찬(Yongchan Kim) 한국지열·수열에너지학회 2010 한국지열에너지학회논문집 Vol.6 No.2
The objective of this study is to find the optimal control algorithm of a hybrid Plant, which is combined by renewable energy plant of the GSHP(Geothermal Source Heat Pump) and the normal plant(chiller, boiler). The work presented in this study was carried out in the EnergyPlus(Version 2.0). The EnergyPlus was modified in order to simulate the hybrid plant. The plant system was controlled by the load-range-based operation in which schemes select a user specified set of equipment for each user specified range of a particular simulation condition. In the use of the load-range-based operation, four kind of control cases were defined and simulated in order to obtain the optimal control algorithm of the hybrid plant. The result showed that the Case 2 was the optimal control algorithm which used the GSHP as a base operating plant and the normal plant as an assistant operating plant. Even though the normal plant was operated in full load and the renewable energy plant of the GSHP was operated in partial load, the annual energy consumption of the normal plant was larger than that of the GSHP plant.
전종욱(Jongug Jeon),김용찬(Yongchan Kim),최종민(Jong Min Choi) 대한설비공학회 2006 대한설비공학회 학술발표대회논문집 Vol.2006 No.6
Electronic and telecommunication industries are constantly trying to develop compact components having high power density. Therefore, a proper heat dissipation method is very important to allow reliable operation of the telecommunication equipment. In this study, a hybrid refrigeration system for a telecommunication equipment room was designed to save energy consumption and improve reliability of the compressor. In addition, the performance of the hybrid refrigeration system was measured with a variation of outdoor load. The designed hybrid refrigeration system for the telecommunication equipment shelter saved the energy approximately 50% at the mode switch temperature of 8.3℃.
지열발전을 위한 지열정 시멘트용 G-class시멘트와 일반 포틀랜드시멘트와의 유동성 비교실험
전종욱(Jongug Jeon),원종묵(Jongmuk Won),최항석(Hangseok Choi) 한국지열·수열에너지학회 2012 한국지열에너지학회논문집 Vol.8 No.2
The G-class cement is usually used for geothermal well grouting to protect a steel casing which is equipped in a geothermal well to transfer geothermal water from deep subsurface to ground surface. In geothermal grouting process, obtaining appropriate fluidity is extremely important in order to fill cement grout flawlessly. In this paper, a series of the V-funnel and Slump Flow test was performed on both of the Portland cement and the G-class cement in order to compare fluidity and filling ability of those kind of cements. In the result of V-funnel test, the fluidity of G-class cement was evaluated much better than the Portland cement at the water/cement ratio of 0.8. In the case of Slump Flow test, the fluidity of G- class cement was estimated slightly better than the Portland cement at both the water/cement ratio of 0.55 and 0.8. Even though the initial fluidity and filling ability of G-class cement were relatively higher than the Portland cement, the results could be considerably changed with time. The results show that the fluidity and filling ability for geothermal well cementation can be properly controlled with water content and additives for adverse geothermal well environment.
지열 발전정 시멘팅을 위한 G-class 시멘트 특성 평강에 관한 연구
원종묵(Won, Jongmuk),전종욱(Jeon, Jongug),박상우(Park, Sangwoo),최항석(Choi, Hangseok) 한국지반공학회 2013 한국지반공학회논문집 Vol.29 No.5
The G-class cement is commonly used on practice for geothermal well cementing in order to protect a steel casing that is designed to transport hot water/steam from deep subsurface to ground surface during operating a geothermal power plant. In order to maintain optimal performance of geothermal wells, physical properties of the cementing material should be satisfactory. In this paper, relevant factors (i.e., groutability, uniaxial compression strength, thermal conductivity and free fluid content) of the G-class cement were experimentally examined with consideration of various water-cement(w/c) ratios. Important findings through the experiments herein are as follows. (1) Groutability of the G-calss cement increases by adding a small dose of retarder. (2) There would be a structural defect caused when the w/c ratio is kept higher in order to secure groutability. (3) Thermal conductivity of the G-class cement is small enough to prevent heat loss from hot steam or water to the outer ground formation during generating electricity. (4) The G-class cement does not form free water channel in cementing a geothermal well. (5) The Phenolphthalein indicator is applicable to the distinction of the G-class cement form the drilling mud.
최종민(Jong Min Choi),전종욱(Jongug Jeon),김용찬(Yongchan Kim),윤린(Yun Rin) 대한설비공학회 2006 대한설비공학회 학술발표대회논문집 Vol.2006 No.11
MPCM (Microencapsulated Phase Change Material) slurries show several advantages over the sensible heat transportation system. In this study, the cooling performance tests of liquid-cooling heat exchanger with MPCM slurries for telecommunication equipment were executed. The maximum surface temperature and IUTM of the silicon rubber heater installed replacing with PCB of telecommunication equipment at the inlet temperature of 19℃ with MPCM slurries was lower than those at the inlet temperatures of 25℃ and 27℃ because the heat capacity and heat transfer rate increased. For MPCM slurries, the enhancement of the heat transfer and the augmentation of heat capacity increased according to the increase of flow rate by a rotational motion of the MPCM particles. The cooling performance of the liquid-cooling heat exchanger with MPCM slurries was more enhanced than it with water.