4면형 아트리움의 광정지수와 방위 및 천창형태에 따른 인접실내공간의 자연채광 성능

Abstract

고유가 저에너지 시대에 접어들면서 건축물의 실내 자연채광의 유입에 대한 연구가 활발히 진행되고 있다. 건물의 자연채광 유입은 에너지절약 뿐만 아니라 재실자에게 쾌적한 빛환경을 제공하는 역할을 한다. 철과 유리의 사용이 보편화 된 산업혁명 이후에 아트리움은 외부와 면하는 공간에 비해 태양열을 적극적으로 이용할 수 있다는 장점이 있기 때문에 많이 이용되어 왔다. 특히 4면형 아트리움은 지붕부분을 유리로 덮은 중정의 개념으로 건물 내부에 자연채광 유입이 용이하여 도서관, 공공기관, 사무소건물 등에 많이 이용되고 있다. 실내에 있는 건물 이용자들로 하여금 자연환경과 같은 분위기를 느낄 수 있고 비와 바람 등을 피할 수 있는 장점이 있어 휴게공간으로 많이 이용되고 있다. 이러한 아트리움과 면한 인접실내공간에서도 아트리움을 통해 유입되는 자연광을 받을 수 있기 때문에, 실내 깊숙한 부분에 위치함에도 불구하고 실외와 같은 분위기를 느낄 수 있다. 본 연구에서는 4면형 아트리움의 시뮬레이션 프로그램 평가를 하기 위하여 아트리움의 건축적 조건을 설정한 후, 아트리움의 설계 변수인 광정지수, 방위, 천창형태에 대하여 DAYSIM 시뮬레이션 프로그램을 이용하여 정적 시뮬레이션인 DF(Daylight Factor)와 동적 시뮬레이션인 DA(Daylight Autonomy), UDI(Useful Daylight Illuminance)를 분석하여 자연채광성능을 평가하였다.

본 논문은 제 1 장 서론, 제 2 장 ∼ 제 4 장의 본론, 제 5 장 결론으로 구성되어 있으며 각 장의 개요는 다음과 같다. 제 1 장에서는 연구의 배경 및 필요성, 연구의 목적, 연구의 범위 및 방법에 대하여 기술하였다. 제 2 장에서는 아트리움의 기본 이론에 대하여 조사하고 자연채광 성능 평가 방법과 조도 측정 시 고려사항에 대하여 기술하였다. 제 3 장에서는 시뮬레이션 프로그램에 대하여 조사하고 아트리움의 주요 변수에 대하여 설정하고 시뮬레이션 조건에 대하여 기술하였다. 제 4 장에서는 제 3 장에서 설정한 변수에 대해 컴퓨터시뮬레이션 프로그램을 통해 아트리움의 인접실내공간의 자연채광 성능을 기술하였다. 제 5 장에서는 본 논문의 결론에 대하여 기술하였다.

본 연구의 결과는 다음과 같이 요약된다.

1) 아트리움에 면한 거주공간에서의 적정 주광률 5% 이상은 전부 만족하였다. 주광률은 담천공일 때의 평가이기 때문에 아트리움 인접공간의 동, 서, 남, 북 방향에 상관없이 아트리움 부분에서 외벽으로의 추세가 비슷하며 외벽의 창문으로 들어오는 주광률이 아트리움에 면한 창문에 의한 자연광의 주광률 값보다 높았다.

2) DA의 경우 500lx이상을 기준으로 하기 때문에 전체적으로 높은 수치를 나타낸다. 따라서 방위에는 크게 영향을 받지 않으며 동과 서, 남과 북은 서로 대칭을 보인다.

3) UDI의 경우 광정지수가 작을수록 거주공간의 실외측 창면에 가까운 부분은 외부 자연광의 영향을 많이 받기 때문에 2000lx이상의 UDI값이 높아져 외벽의 창문 부분은 낮은 수치를 나타낸다. 특히, 톱니형 천창의 경우 개구부 방위와 아트리움의 상부에 있는 인접 거주공간의 위치관계에 따라 아트리움 내부 창문을 통해 유입되는 자연광의 양에 큰 차이를 보였다.|Studies on daylighting of buildings have been continuously increased due to the recent escalating oil price and low-carbon strategies in developed countries. Daylighting of buildings not only saves electric energy, but provide the occupants with a comfort visual environment. Atrium has been widely used since industrial revolution when the use of iron and glass were common as it has an advantage that it can effectively utilize solar heat compared to the adjacent space to the outside. Especially, four-sided atrium, as a concept of courtyard with glass covered roof, is widely used as a resting place because of its merit, allowing the users of building to feel atmosphere of natural environment and to take a shelter from rain and wind. Atrium spaces are adopted by many modern buildings to improve daylight performance of deep interior spaces. Among the various types of atria, the four-sided type atrium is frequently adopted by library buildings, governmental buildings and office buildings. Even the adjacent occupied space to atrium can have daylight through atrium while making visitors feel as if they are outside in spite that it is located deep inside of building. This study aims to suggest daylighting design data for adjacent occupied spaces by conducting dynamic simulations using Daysim program. Daylight Factor(DF), Daylight Autonomy(DA) and Useful Daylight Illuminance(UDI) levels for 12 measurement points in adjacent occupied spaces were calculated for square-shape four-sided atria with different WI(Well Index),orientation and different canopy systems.

This study consists of a total of five chapters, and each chapter can be summarized as follows: In Chapter 1, the background, the purpose, the scope and the method of this study were described. In Chapter 2, In this study, the underlying theory of atrium was surveyed to suggest how to assess the Daylight performance and considerations to measure the illuminance. In Chapter 3, This study surveyed the program, set up the key variables of atrium and described simulation conditions. In Chapter 4, Even the adjacent occupied space to atrium can have daylight through atrium while making visitors feel as if they are outside in spite that it is located deep inside of building. In Chapter 5, the conclusion of the study were stated.

The study results are summarized as follows:

1) All residential spaces adjacent to atrium satisfied proper daylight factor 5%. As the daylight factor is an estimate in overcast sky, the trend as an outer wall was similar regardless of orientation adjacent to atrium and the daylight factor from the window of outer wall was higher than that of daylight coming through the window adjacent to atrium.

2) As DA requires more than 500lx, it shows higher overall. Therefore, it is not significantly affected by orientation, and showed symmetric for east and west, south and north.

3) In case of UDI, the lower WI is, the more outdoor space is affected by daylight. Therefore, UDI value reaches to over 2000lx, so the window of outer wall shows low value. Especially, differently from the flat type skylight, the sawtooth skylight is more affected by the light coming through the skylight when WI is high.; Studies on daylighting of buildings have been continuously increased due to the recent escalating oil price and low-carbon strategies in developed countries. Daylighting of buildings not only saves electric energy, but provide the occupants with a comfort visual environment. Atrium has been widely used since industrial revolution when the use of iron and glass were common as it has an advantage that it can effectively utilize solar heat compared to the adjacent space to the outside. Especially, four-sided atrium, as a concept of courtyard with glass covered roof, is widely used as a resting place because of its merit, allowing the users of building to feel atmosphere of natural environment and to take a shelter from rain and wind. Atrium spaces are adopted by many modern buildings to improve daylight performance of deep interior spaces. Among the various types of atria, the four-sided type atrium is frequently adopted by library buildings, governmental buildings and office buildings. Even the adjacent occupied space to atrium can have daylight through atrium while making visitors feel as if they are outside in spite that it is located deep inside of building. This study aims to suggest daylighting design data for adjacent occupied spaces by conducting dynamic simulations using Daysim program. Daylight Factor(DF), Daylight Autonomy(DA) and Useful Daylight Illuminance(UDI) levels for 12 measurement points in adjacent occupied spaces were calculated for square-shape four-sided atria with different WI(Well Index),orientation and different canopy systems.

This study consists of a total of five chapters, and each chapter can be summarized as follows: In Chapter 1, the background, the purpose, the scope and the method of this study were described. In Chapter 2, In this study, the underlying theory of atrium was surveyed to suggest how to assess the Daylight performance and considerations to measure the illuminance. In Chapter 3, This study surveyed the program, set up the key variables of atrium and described simulation conditions. In Chapter 4, Even the adjacent occupied space to atrium can have daylight through atrium while making visitors feel as if they are outside in spite that it is located deep inside of building. In Chapter 5, the conclusion of the study were stated.

The study results are summarized as follows:

1) All residential spaces adjacent to atrium satisfied proper daylight factor 5%. As the daylight factor is an estimate in overcast sky, the trend as an outer wall was similar regardless of orientation adjacent to atrium and the daylight factor from the window of outer wall was higher than that of daylight coming through the window adjacent to atrium.

2) As DA requires more than 500lx, it shows higher overall. Therefore, it is not significantly affected by orientation, and showed symmetric for east and west, south and north.

3) In case of UDI, the lower WI is, the more outdoor space is affected by daylight. Therefore, UDI value reaches to over 2000lx, so the window of outer wall shows low value. Especially, differently from the flat type skylight, the sawtooth skylight is more affected by the light coming through the skylight when WI is high.