직접공급방식 지역난방시스템의 적정공급압력 검토

정용호(Jung Yong-Ho),손장열(Sohn Jang-Yeul) 한국건축친환경설비학회 2009 한국건축친환경설비학회 논문집 Vol.3 No.3

District Heating System(DHS) is one of the most excellent systems in terms of energy saving and environmental protection. The current indirect connection in Korea is applied to the case of big scale, it brings about heat loss in its network. Moreover, high-priced heat exchanger facilities are required. Direct connection has some advantages such as energy saving and low initial cost compared with indirect connection since heat exchange is not required in machine room. However, direct connection is not economical for heavy load and it is difficult to keep the temperature of supply water low. When direct connection is applied, it is the most important to supply stable heat source to consumers. Therefore, the objective of this study is to offer the fundamental data for applying the direct connection in district heating to Korea by investigating the pressure variation based on supply condition and stability for consumers from the previous studies. The results of this study are follows; I) In case the supply pressure is 6bar, direct connection is feasible for 5-floor-apartments and detached houses without booster pump by the analysis of pressure variation at consumer facilities. 2) 5~6bar was required in 10-floor-apartments for direct connection and in case of 15-floor apartments, 6bar was necessary to prevent minus pressure without booster pump. 3) In case of 20-floor-apartments, supply pressure of 6bar could not be applied since minus pressure occurred in the top of the apartments.

태양집열창방식 자연환기시스템에 의한 실내 환기효율 예측

정용호(Jung Yong-Ho) 한국건축친환경설비학회 2008 한국건축친환경설비학회 논문집 Vol.2 No.1

This study estimates ventilation efficiency for apartment using solar radiation in order to improve energy savings and indoor air environment. Field measurements were performed in a full-scale mock-up model. A solar collection device and ordinary device for natural ventilation were installed in each room. Temperature and airflow velocity were monitored in each five minutes. Solar radiation and daylight illuminance were also measured. The concentration of indoor air for two conditions was monitored using a multi-gas monitor and tracer gas. The air change rates per hour(ACH) under the conditions were computed based on the concentrations. The air change rates per hour (ACH) using solar radiation exceeded the required air change rate per hour was linearly proportional to the solar radiation. The ventilation device using solar radiation contributed to provide better thermal environment with energy savings. From the result of ventilation efficiency prediction for the 85㎡ area of practical residential building by CFD simulation. it was found that average age of air was 90.3min, nominal time constant was 82.9min. So total average ventilation efficiency was 0.918, this value means about 92% of indoor air could be mixed.

현장측정에 의한 데이터센터 서버실의 냉각시스템 분석

정용호(Jung, Yong-Ho) 한국건축친환경설비학회 2012 한국건축친환경설비학회 논문집 Vol.6 No.1

Energy Cost has been rapidly increased with the internal heat gain of data center to keep the temperature condition. But the cooling units for server systems are fully operated to satisfy the indoor temperature condition, it results in the excessive energy consumption. In this study, various cooling systems were studied for data center and cold aisle containment system was proved to be the best solution for server cooling system. Because it protects the cooling zone from the hot aisle space. Effective cooling and prohibition of recirculation air from hot aisle was possible by the cold aisle containment system.

CdS 광센서를 활용한 CO₂ 레이저의 출력변동율 개선을 위한 실시간 제어

정용호(Yong-Ho Jung),최진영(Jin-Young Choi),정현주(Hyun-Ju Chung),송건주(Gun-Ju Song),김휘영(Whi-Young Kim),강욱(Uk-Kang),김희제(Hee-Je Kim) 대한전기학회 2002 대한전기학회 학술대회 논문집 Vol.2002 No.7

모듈러 데이터센터 냉각시스템의 취출온도 조건에 의한 연간에너지 소비량 예측

정용호(Yong-Ho Jung) 한국생활환경학회 2021 한국생활환경학회지 Vol.28 No.1

The modular data center is greatly influenced by operating conditions because its internal size is smaller than the existing hyperscale data center. The recent emergence of servers that can adapt well to indoor temperature rise requires a review of existing temperature conditions. In this study, the potential for temperature condition mitigation and annual energy performance were analyzed for recent installations of improved thermal performance servers in container-type distributed modular data centers. According to the analysis, the upper dry bulb temperature of the intake air for maintaining the recommended level, acceptable level A1, and acceptable level A2 was 14℃, 16℃, and 19℃ respectively. The annual energy savings predicted in the analysis was 3.1% and 9.2%, when the intake air temperature of the servers in the modular data center was mitigated to the A1 and A2 levels respectively.

분리막 제습공조시스템의 내부 유동 해석에 관한 연구

정용호(Yong-Ho Jung),박성룡(Seong-Ryong Park) 대한설비공학회 2015 설비공학 논문집 Vol.27 No.12

The summer climate is very hot and humid in Korea. Humidity is an important factor in determining thermal comfort. Recently, research on dehumidification device development has been attempted to save the energy required for operating the dehumidifier. Existing dehumidification systems have disadvantages such as wasting energy to drive the compressor. Meanwhile, dehumidification systems with membranes can dehumidify humid air without increasing the dry bulb temperature. Therefore. they don’t have to consume cooling energy. In this paper, the installation conditions for a membrane system were analyzed to improve the shape and optimum performance of the system. The results showed that the distance between elements was the critical system design factor, and that a distance of 20 mm was the optimal condition for the pressure drop and flow characteristics of the internal air flow.

공조시스템의 오염 현황에 대한 실측

정용호(Yong-Ho Jung),안병욱(Byung-Wook Ahn) 한국생활환경학회 2003 한국생활환경학회지 Vol.10 No.1

Air conditioning systems are indispensable in modem buildings. Therefore air conditioning systems play a main role in improving indoor air quality. However, there is not enough information about air duct contamination and any official maintenance standards or guidelines, for air duct maintenance does not exist in Korea. In this study, dust concentration and microorganisms between the upstream and the downstream of air filters and air duct were measured with particle counter and blood agar plates. Before and after duct cleaning out and after 45 days above items were measured at 4 points in each floor of building under actual operating conditions. As for the results, air duct contamination strongly influence on the indoor air quality. So proper maintenance of air duct should be carried out in the building. The aims of this study are proposal for air filter maintenance methods after installation and basic data about air duct maintenance guidelines or standards for operator.

냉복도 밀폐시스템을 적용한 서버실의 실내온도조건

정용호(Yong-Ho Jung),장현재(Hyun-Jae Chang),서장후(Jang-Hoo Seo) 대한설비공학회 2013 설비공학 논문집 Vol.25 No.2

In this study, a cold aisle containment system was proposed among various strategies to reduce the energy waste by recirculation air from the hot aisle. To verify the effectiveness of the cold aisle containment system, a test bed which is similar to an actually existing server room was set up in the Internet Data Center(IDC) building. Comparative experiments, conventional open type cooling system and cold aisle containment system were carried out under actual conditions. The result revealed that the range of inlet temperature of the server system was 20~ 25℃ in an existing cooling system and the range of inlet temperature dropped below 20℃ by the cold aisle containment system. After all, cold aisle containment system was proved to be the solution for energy saving cooling system.

직접공급방식 지역난방시스템의 적정공급온도 및 단위부하 분석

정용호(Jung Yong-Ho) 한국건축친환경설비학회 2010 한국건축친환경설비학회 논문집 Vol.4 No.3

District Heating System(DHS) is one of the most excellent systems in terms of energy saving and environmental protection. The current indirect connection in Korea is applied to the case of big scale, it brings about heat loss in its network. Moreover, high-priced heat exchanger facilities are required. Direct connection has some advantages such as energy saving and low initial cost compared with indirect connection since heat exchange is not required in machine room. Furthermore, renewable energy such as solar heat, geo-thermal heat and heat pump and others can be applied to the direct connection in district heating as supply temperature is comparatively low. However, direct connection is not economical for heavy load and it is difficult to keep the temperature of supply water low. When direct connection is applied, it is the most important to supply stable heat source to consumers. In the previous study, appropriate supply pressure for direct connection are suggested. Therefore, the objective of this study is to offer the fundamental data for applying the direct connection in district heating to Korea by investigating the unit heating load and optimal temperature based on supply condition and stability for consumers from the previous studies. The results of this study are follows; 1) Heating loads(including domestic hot water supply) for each consumers in conventional direct connection system were proved to be excessive comparing to simulated results. 2) The optimal range of supply water temperature was 60~90℃ in case of supply for domestic hot water to each households.

분리막 제습공조시스템의 잠열부하 저감효과 예측

정용호(Yong-Ho Jung),박성룡(Seong-Ryong Park) 대한설비공학회 2017 설비공학 논문집 Vol.29 No.1

The summer climate is very hot and humid in Korea. The humidity is an important factor in determining thermal comfort. Recently, the research for dehumidification device development has been attempted to save energy that is required for the operation of the current dehumidifiers on the market. Existing dehumidification systems have disadvantages such as wasting energy to drive a compressor. Meanwhile, dehumidification systems with membranes can dehumidify humid air without increasing the dry bulb temperature so it doesn’t have to consume cooling energy. In this paper, the cooling energy savings was studied when a dehumidification system was applied in a model building instead of a chiller. The sensible heat load was almost the same result, but the latent heat load was decreased by 38.9% and the total heat load was decreased by 8.5%. As a result, electric energy used to drive the compressor in a chiller was saved by applying a membrane airconditioning system instead.