열교환방식에 따른 지열히트펌프의 난방특성에 관한 연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon),박차식(Cha Sik Park) 한국지열·수열에너지학회 2012 한국지열에너지학회논문집 Vol.8 No.2

The objective of this study is to investigate the influence on the heating performance for a water-to-water 10RT ground source heat pump by using the water switching and refrigerant switching method. The test of water-to-water ground source heat pump was measured by varying the compressor speed, load side inlet temperature, and ground heat source side temperature. The heating capacity and COP of the heat pump increased with increasing ground heat source temperature. As a result, compared to a refrigerant switching method, the water switching method with counter flow improves the heating capacity and COP by approximately 5% in average, respectively.

탄산칼슘을 이용한 판형열교환기의 파울링 생성 및 제거 특성

차동안(Dong-An Cha),배경진(Kyung-Jin Bae),권오경(Oh-Kyung Kwon),설원실(Won-Sil Seol) 대한기계학회 2014 대한기계학회 춘추학술대회 Vol.2014 No.11

마이크로 웨이브 냉각수를 이용한 히트펌프 건조기의 건조특성

차동안(Dong An Cha),배경진(Kyung Jin Bae),권오경(Oh Kyung Kwon) 대한기계학회 2016 대한기계학회 춘추학술대회 Vol.2016 No.4

흡착제 코팅 바인더 비율 변화에 따른 유효열전도율 측정

차동안(Dong-An Cha),배경진(Kyung-Jin Bae),권오경(Oh-Kyung Kwon),오명도(Myung-Do Oh) 대한설비공학회 2016 대한설비공학회 학술발표대회논문집 Vol.2016 No.6

[학술강연] 2중 PVC배관제의 소음특성에 관한 연구

차동안(Dong-An Cha),김재돌(Jae-Dol Kim),장재은(Jae-Eun Jang),윤정인(Jung-In Yoon) 한국마린엔지니어링학회 2002 한국마린엔지니어링학회 학술대회 논문집 Vol.2002 No.-

A solution about noise of every kind happening in the inner part of a building is not very sufficient. Especially, because of diversity about living, consumption of water in a building of every kind is on the increase, and most of used water operate as drainage load. In this process, drainage noise in the drainage pipe laying generated frequently from a bathroom, a kitchen, or a various room of an apartment house like a various generation house, an apartment, villa, and a commercial building like a hotel, a motel is deteriorated a human desire about an easy life in a snug space, and extremely, it is also raise trouble each other. Accordingly, in this study, we work and set up as double structure about PVC pipe laying used of pipe laying materials in drainage pipe laying for a building of every kind, and we furnished data about drainage pipe laying noise reduction through an comparison experiment between data of research materials and that of existing about a specific character of drainage noise generated from drainage of a chamber pot and a bath tub in the building.

제어방식에 따른 반도체 공정용 칠러에 관한 연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

Excessive heat may occur during semiconductor manufacturing process. Thus, precise control of temperature is required to maintain constant ambient-temperature and also wafer-temperature in the chamber. Compared to an industrial chiller, semiconductor chiller's power consumption is very high due to its continuous operation for a year. Considering the high power consumption, it is necessary to develop an energy efficiency chiller by optimizing operation control. Therefore, in this study, an experimental study is conducted to determine the optimal refrigerant charge for the semiconductor chiller. The performance of PWM and EEV method chiller, are compared through the experiments, refrigerant circulation rate, temperature rise and fall, control precision. Optimum charge of refrigerant for the cooling capacity, 3.7 ㎾ was measured as 3.5 ㎏. For the EEV-chiller, power consumption, refrigerant circulation rate, and system pressure tends to increase. For the experiment of temperature rise and fall, the EEV-chiller takes the time of 39minutes, and the power consumption of 3.52 ㎾. For the precise control experiment, at the temperature of 0℃ the deviations are ±0.5℃ for PWM method, ±1.5℃ for EEV method.

세라믹 볼을 이용한 판형열교환기 세정에 관한 실험적 연구

차동안(Dong-An Cha),권오경(Oh-Kyung Kwon),채희만(Hee-Man Chae),권정태(Jeong-Tae Kwon),설원실(Won-Sil Seol) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12

To maintain efficiency of heat exchanger, fouling of heat transfer surface is important to remove. This study was to investigate cleaning result of plate heat exchanger using ceramic ball. The fouling is created in heat transfer surface of plate heat exchanger using CaCO₃ as the fouling subject. The fouling concentration varied from 10 mol/m³ to 20 mol/m³. The overall heat transfer coefficient recovered 97.9% for 10mol/m³ case, and 94.3% for 20 mol/m³ case in comparison with initial state. It can be concluded that the cleaning of ceramic ball contribute significantly to the of performance recovery for overall heat transfer coefficient and fouling resistance after cleaning experiment.

듀얼채널을 적용한 반도체공정용 칠러의 실험적 연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon) 대한설비공학회 2010 설비공학 논문집 Vol.22 No.11

Excessive heat occurs during semiconductor manufacturing process. Thus, precise control of temperature is required to maintain constant chamber-temperature and also wafertemperature in the chamber. Compared to an industrial chiller, semiconductor chiller’s power consumption is very high due to its continuous operation for a year. Considering the high power consumption, it is necessary to develop an energy efficient chiller by optimizing operation control. Therefore, in this study, a semiconductor chiller is experimentally investigated to suggest energysaving direction by conducting load change, temperature rise and fall and control precision experiments. The experimental study shows the cooling capacity of dual-channel chiller rises over 30% comparing to the conventional chiller. The time and power consumption in the temperature rising experiment are 43 minutes and 8.4 kWh, respectively. The control precision is the same as ±1℃ at 0℃ in any cases. However, it appears that the dual channel’s control precision improves to ±0.5℃ when the setting temperature is over 30℃.

지열히트펌프 시스템의 난방운전 특성에 관한 실증연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon),박성구(Sung Gu Park) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.5

EEV를 적용한 열교환방식별 지열히트펌프의 냉난방 특성

차동안(Dong An Cha),권오경(Oh Kyung Kwon),박성구(Sung Gu Park) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.5

본 연구의 목적은 EEV를 적용한 냉매절환과 수 절환에 의해 변하는 10RT급 지열히트펌프의 성능을 평가하고자 하볐다. 지열히트펌프의 냉난방 용량 및 성능실험은 10RT급 물 대 물 지열히트펌프의 EEV의 개도변화를 통하여 파악하였다. 본 히트펌프는 EEV의 개도가 커질수록 COP 및 냉난방능력이 상승하는 것을 확인하였다. 결과적으로, 대항류 수절환 방식이 냉매 절환 방식에 비해 평균적으로 약 5~8% 로 COP와 냉난방능력이 높은 것을 확인하였다. The objective of this study is to investigate the influence of the cooling and heating performance for a water-to-water 10RT ground source heat pump by using the water switching and refrigerant switching method for EEV. The test of water-to-water ground source heat pump cooling, heating capacity and COP was measured by varying the EEV open degree. The cooling, heating capacity and COP of the heat pump increased with increasing EEV open degree. As a result, compared to a refrigerant switching method, the water switching method with counter flow improves the cooling, heating capacity and COP by approximately 5~8% in average, respectively.