Multi Axis DOAS를 이용한 대기미량 물질 원격 측정

이철규 ( Chul Kyu Lee ),김영준 ( Young Joon Kim ) 大韓遠隔探査學會 2006 大韓遠隔探査學會誌 Vol.22 No.2

태양광을 광원으로 하고 천정방향을 포함한 다양한 고도각을 이용하는 자외선/가시광선영역에서의 흡수분광학이 최근에 지상용 대기원격 측정에 개발되어오고 있다. 이를 이용하여 지표부근에 존재하는 대기 미량 물질의 공간적 분포가 유추될 수 있다. 대기질 측정기술 중 하나인 MAX-DOAS (Multi-axis Differential Optical Absorption Spectroscopy) 기술은 광원으로서 태양산란광을 이용하고, 다양한 고도각에서 태양산란광을 기록하고 분석을 통하여 대기 중 미량 물질을 측정한다. 광주과학기술원 환경모니터링신기술 연구센터에서 개발된 MAX-DOAS 시스템은 2004년 1월, 5월, 10월에 각각 도시대기, 화산플룸, 화력발전소 플룸의 측정에 적용되었다. 각각의 경우에 SO2, NO2, BrO, O4를 정량분석하기 위하여 기록된 MAX-DOAS 스펙트럼은 자외선/가시광선 영역에서의 고유 흡수스펙트럼을 이용한 DOAS 기술을 이용하여 분석 되었다. 그 결과는 Slant Column Density (SCD)로 표현되었다. 플룸 측정의 경우에서는 플룸 속에 포함된 NO2, SO2의 공간적 분포를 파악하기 위하여 플룸의 진행방향과 수직적인 방향에서 MAX-DOAS 스캔이 이루어졌다. 이를 통하여 얻은 단면적을 토대로 SO2, NO2 농도가 계산되었다. 화산플룸에서 SO2는 580ppbv, 화력발전소 플룸에서 NO2는 337ppbv, SO2는 227 ppbv로 계산되었다. UV-visible absorption measurement techniques using several horizone viewing directions in addition to the traditional zenith-sky pointing have been recently developed in ground-based remote sensing of atmospheric constituents. The spatial distribution of various trace gases close to the instrument can be derived by combing several viewing directions. Multi-axis differential optical absorption spectroscopy (MAX-DOAS) technique, one of the remote sensing techniques for air quality measurements, uses the scattered sunlight as a light source and measures it at various elevation angles (corresponding to the viewing directions) by sequential scanning with a stepper motor. A MAX-DOAS system developed by GIST/ADEMRC has been applied to measuring trace gases in urban air and plumes of the volcano and fossil fuel power plant in January, May, and October 2004, respectively. MAX-DOAS spectra were analyzed to identify and quantify SO2, NO2, BrO, and O4 (based on Slant Column Densities, SCD) in the urban air, volcanic plume, and fossil fuel power plant utilizing theirs specific structured absorption features in the UV-visible region. Vertical scan through the multiple elevation angles was performed at different directions perpendicular to the plume dispersion to retrieve cross-sectional distribution of SO2 or NO2 in the plumes of the volcano and fossil fuel power plant. Based on the estimated cross sections of the plumes the mixing ratios were estimated to 580 SO2 ppbv in the volcanic plume, and 337 NO2 and 227 SO2 ppbv in the plume of the fossil fuel power plant, respectively.

외기전담시스템 기반 초고층 공동주택 중앙 공급식 환기시스템의 적정 급기조건 설정 및 에너지 절감효과 분석

정재원(Jeong Jae-Weon),김민휘(Kim Min-Hwi),김유신(Kim Yu-Sin),김진효(Kim Jin-Hyo),권오현(Kwon Oh-Hyun) 대한건축학회 2009 대한건축학회논문집 Vol.25 No.6

The main thrust of this paper is to investigate optimized supply air conditions and energy saving potentials of a dedicated outdoor air system (DOAS) applied to a highrise apartment building. As for a typical 132-m2 apartment unit, it was assumed that two different systems; centralized DOAS-Ceiling Radiant Cooling Panel and decentralized Energy Recovery Ventilator-Packaged Air Conditioner were installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program, and annual cooling coil load and heating load reduction potentials were compared. It was found in this research that DOAS-Ceiling Radiant Cooling Panel system can reduce the cooling coil load over 21% annually compared with the current Energy Recovery Ventilator-Packaged Air Conditioner pair. In addition, over 40% of annual ventilation heating load can be reduced by use of DOAS when the enthalpy wheel and the sensible wheel of the DOAS unit operate simultaneously. It was also found that the optimized dew point temperature of the DOAS supply air accommodating total latent load of a space is 11-12℃.

초고층 공동주택 외기전담 시스템 기반 중앙 공급식 환기시스템의 적정 급기조건 설정

김민휘(Kim Min-Hwi),김진효(Kim Jin-Hyo),권오현(Kwon Oh-Hyun),정재원(Jeong Jae-Weon) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.2009 No.11월

The main thrust of this paper is to investigate acceptable supply air conditions of a dedicated outdoor air system (DOAS) for highrise apartment buildings. As for a typical 132-㎡ apartment unit, it was assumed that centralized DOAS-Ceiling Radiant Cooling Panel was installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program. The optimized dew point temperature of the DOAS was discussed on the basis of the ASHRAE standard 62.1-2007 and the current Korean ventilation standard for apartments. It was found that the optimized dew point temperature of the DOAS supply air accommodating total latent load of a space is 11-12℃ and the appropriate supply air temperature of the DOAS is 11-12℃ in cooling period and neutral temperature of 18-20℃ in intermediate period.

외기전담 시스템 기반 초고층 공동주택 중앙 환기시스템의 에너지 절감효과 분석

김진효(Kim Jin-Hyo),권오현(Kwon Oh-Hyun),정재원(Jeong Jae-Weon),김민휘(Kim Min-Hwi) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.2009 No.11월

This paper investigates the energy saving potentials of a dedicated outdoor air system (DOAS) applied to a highrise apartment building. As for a typical 132-㎡ apartment unit, two different HVAC systems; centralized DOAS-Ceiling Radiant Cooling Panel and decentralized Energy Recovery Ventilator-Packaged Air Conditioner were installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program, and annual cooling coil load and heating load reduction potentials were compared. The research shows that DOAS-Ceiling Radiant Cooling Panel system can reduce the cooling coil load over 21% annually compared with the current Energy Recovery Ventilator-Packaged Air Conditioner pair. In addition, over 40% of annual ventilation heating load can be reduced by use of DOAS.

국내 여름철 기후조건에서 DOAS와 TABS 통합시스템 냉방운전시 실내온열환경 및 운전특성 평가

이윤선(Lee, YoonSun),이겨레(Lee, Keo-Re),정웅준(Chung, Woong June),임재한(Lim, Jae-Han) 대한건축학회 2018 대한건축학회논문집 Vol.34 No.11

To reduce the energy consumption of HVAC system in buildings, thermally activated building system(TABS) has been applied to low energy building because of energy efficient performance and reduction of peak load. DOAS coupled with a parallel sensible cooling could be promising because TABS handles sensible heat load only. The purpose of this study was to evaluate the indoor thermal environment and cooling operation characteristic of TABS with dedicated outdoor air system(DOAS) in Korea climate. Indoor thermal environment and operation characteristic of TABS integrated with DOAS are investigated at different TABS operation schedules and climate conditions by simulation tests. The result shows that the DOAS is more suitable for hot and humid climates. And also it show that the potential of intermittent operation of TABS.

외기전담시스템의 병원건물에 대한 적용성 및 냉난방 에너지 절감 효과에 관한 연구

김민휘(Kim Min-Hwi),김진효(Kim Jin-Hyo),권오현(Kwon Oh-Hyun),석윤진(Seok Yoon-Jin),정재원(Jeong Jae-Weon) 한국건축친환경설비학회 2009 한국건축친환경설비학회 논문집 Vol.3 No.4

The purpose of this paper is to investigate supply air conditions and energy saving potentials of a dedicated outdoor air system (DOAS) applied to a patient room of health care facilities. The design of HVAC systems for healthcare facilities is a specialized field of engineering. Based on the current health care facilities design satandards, it was assumed that four 25.8m2 unit patient rooms are served by the three different HVAC systems; a constant air volume system(CAV) with fan coil unit(FCU), a variable air volume system (VAV), and a dedicated outdoor air system (DOAS) with fan coil unit (FCU). Control strategies and energy saving potentials of each system were modeled and estimated using the TRNSYS 16 energy simulation program. Annual cooling and heating coil loads and fan energy reduction were calculated. It was found that the DOAS+FCU system can reduce the fan energy consumption over 65% annually compared with the conventional CAV+FCU system. In addition, over 57.5% of annual cooling coil load can be reduced by use of DOAS+FCU system.

병원건물의 환기특성을 고려한 외기전담시스템의 에너지 절감 효과 예측

김민휘(Kim Min-Hwi),김진효(Kim Jin-Hyo),권오현(Kwon Oh-Hyun),석윤진(Seok Yoon-Jin),정재원(Jeong Jae-Weon) 한국건축친환경설비학회 2010 한국건축친환경설비학회 학술발표대회 논문집 Vol.2010 No.3

The purpose of this paper is to investigate supply air conditions and energy saving potentials of a dedicated outdoor air system (DOAS) applied to a patient room of health care facilities. The design of HVAC systems for healthcare facilities is a specialized field of engineering. Based on the current health care facilities design satandards, it was assumed that four 25.8m2 unit patient rooms are served by the three different HVAC systems; a constant air volume system(CAV) with fan coil unit(FCU), a variable air volume system (VAV), and a dedicated outdoor air system (DOAS) with fan coil unit (FCU). Control strategies and energy saving potentials of each system were modeled and estimated using the TRNSYS 16 energy simulation program. Annual cooling and heating coil loads and fan energy reduction were calculated. It was found that the DOAS+FCU system can reduce the fan energy consumption over 65% annually compared with the conventional CAV+FCU system. In addition, over 57.5% of annual cooling coil load can be reduced by use of DOAS+FCU system.

외기전담시스템의 소요 전력 공급을 위한 PV array 면적 산정 프로그램 개발

김진효(Kim Jin-Hyo),김민휘(Kim Min-Hwi),권오현(Kwon Oh-Hyun),석윤진(Seok Yoon-Jin),정재원(Jeong Jae-Weon) 한국태양에너지학회 2010 한국태양에너지학회 학술대회논문집 Vol.2010 No.11

The main thrust of this paper is to develop photovoltaic(PV) array area and electricity to delivered estimation program applicable to dedicated outdoor air system(DOAS) design. The proposed program was derived as a function of electrical load required to DOAS operation, tilt and azimuth angle of PV array and total incident solar radiation on a horizontal surface at a given location. The electrical loads of DOAS serving a high-rise apartment building were estimated and a numerical model returning daily electrical energy consumption of a DOAS was derived. Total incident solar radiation on a horizontal surface at any given location were also estimated using an existing solar radiation prediction model. The predicated PV array area and electricity to delivered were very similar to that of the real case and would be used at the design phase of the DOAS.

Active Chilled Beam의 외기량 선정과 최적 시스템 구성에 관한 연구

송진용(Song, Jin-Yong),정재훈(Chung, Jae-Hoon) 대한건축학회 2013 대한건축학회논문집 Vol.29 No.5

In order to decrease consumption of heating and cooling energy in building, the active chilled beam system which provides excellent thermal comfort, energy saving and efficient use of space due to high heat capacity of water used as heat transfer medium are primarily used in Europ and North America. Recently, the active chilled beam system is used to save consumption of energy in buildings. But design data and rules of the active chilled beam system in domestic is lack. So this study proposes to how to select appropriate primary airflow rate to national standard. The chilled beam systems are classified Dedicated Outdoor Air System(DOAS) configurations of 9 types in Seoul, Daegu, Jeju that is able to design in domestic and analyzed consumption of energy by Trace700 program.

GEMS 이산화황 산출 현업 알고리즘에서 오프셋 보정 계수 산정 방법에 대한 영향 조사

박정현 ( Jeonghyeon Park ),양지원 ( Jiwon Yang ),최원이 ( Wonei Choi ),김세린 ( Serin Kim ),이한림 ( Hanlim Lee ) 대한원격탐사학회 2022 大韓遠隔探査學會誌 Vol.38 No.2

본 연구에서는 지난 2020년 2월에 발사된 정지궤도환경위성탑재체(Geostationary Environment Monitoring Spectrometer; GEMS)의 이산화황 산출 현업 알고리즘에서 오프셋 보정 계수 산정 방법이 이산화황 칼럼 농도 산출 결과에 미치는 영향을 확인하였다. GEMS의 현업 이산화황 산출 알고리즘은 차등흡수분광법(Differential Optical Absorption Spectroscopy; DOAS)과 주성분분석방법(Principal component analysis; PCA)이 융합된 하이브리드 알고리즘이다. 하이브리드 알고리즘에서는 차등흡수분광법을 이용하여 스펙트럴 피팅 후 나오는 이산화황 경사층적분농도 값에 나타나는 오존에 의한 흡수 영향을 보정하기 위하여 편차 보정 과정을 필수적으로 거치게 되며, 오프셋 보정 계수를 산정하는 조건에 따라 이산화황 칼럼농도 산출결과가 달라질 수 있기 때문에 적절한 오프셋 보정 계수 값의 적용이 필요하다. 본 연구에서는 구름 화소가 많이 존재하는 날짜와 적게 존재하는 날짜에 대해 오존 보정 계수를 각각 계산하고, 각각의 오존 보정 계수를 GEMS 현업 이산화황 산출 알고리즘에 적용하여 산출한 이산화황 칼럼농도의 비교를 수행하였다. 구름 화소가 많이 존재하는 날의 GEMS 복사휘도 자료를 이용하여 계산된 오존 보정 계수를 사용한 경우, GEMS 관측 영역의 가장자리에 해당하는 인도 부근에서의 이산화황 칼럼농도의 표준편차가 1.27 DU, 한반도 부근에서 0.58 DU, 주변에 구름 화소가 많았던 홍콩 부근에서 0.77 DU로 나타났다. 한편, 구름 화소가 적은 날의 GEMS 자료를 이용하여 계산된 오존 보정 계수를 사용하였을 경우의 이산화황 칼럼농도의 표준편차는 인도주변에서 0.72 DU, 한반도 주변에서 0.38 DU, 홍콩 부근에서 0.44 DU로 다소 감소하였음을 확인하였으며, 구름 화소가 많은 날의 오존 보정 계수를 사용하여 이산화황을 산출한 경우 대비 비교적 안정적인 산출이 이루어졌음을 확인하였다. 이에 따라, GEMS 이산화황 산출 알고리즘의 불확실성 최소화 및 안정적인 산출을 위해서 적절한 조건에서의 오존 보정 계수 산정이 이루어져야 할 필요가 있다. In this present study, we investigated the effect of the offset correction factor calculation method on the sulfur dioxide (SO₂) column density in the SO₂ retrieval algorithm of the Geostationary Environment Monitoring Spectrometer (GEMS) launched in February 2020. The GEMS operational SO₂ retrieval algorithm is the Differential Optical Absorption Spectroscopy (DOAS) - Principal Component Analysis (PCA) Hybrid algorithm. In the GEMS Hybrid algorithm, the offset correction process is essential to correct the absorption effect of ozone appearing in the SO₂ slant column density (SCD) obtained after spectral fitting using DOAS. Since the SO₂ column density may depend on the conditions for calculating the offset correction factor, it is necessary to apply an appropriate offset correction value. In this present study, the offset correction values were calculated for days with many cloud pixels and few cloud pixels, respectively. And a comparison of the SO₂ column density retrieved by applying each offset correction factor to the GEMS operational SO₂ retrieval algorithm was performed. When the offset correction value was calculated using radiance data of GEMS on a day with many cloud pixels was used, the standard deviation of the SO₂ column density around India and the Korean Peninsula, which are the edges of the GEMS observation area, was 1.27 DU, and 0.58 DU, respectively. And around Hong Kong, where there were many cloud pixels, the SO₂ standard deviation was 0.77 DU. On the other hand, when the offset correction value calculated using the GEMS data on the day with few cloud pixels was used, the standard deviation of the SO₂ column density slightly decreased around India (0.72 DU), Korean Peninsula (0.38 DU), and Hong Kong (0.44 DU). We found that the SO₂ retrieval was relatively stable compared to the SO₂ retrieval case using the offset correction value on the day with many cloud pixels. Accordingly, to minimize the uncertainty of the GEMS SO₂ retrieval algorithm and to obtain a stable retrieval, it is necessary to calculate the offset correction factor under appropriate conditions.