A model has been developed to predict natural ventilation in a single zone building with large openings. This study first presents pressure-based equations on natural ventilation, that include the combined effect of wind and thermal buoyancy. Moreover, the concept of neutral pressure level(NPL) is introduced to consider the two-way flow through a large opening. The total pressure differences across the opening and the NPL are calculated, and nonlinear equations are solved to find the zonal pressure to satisfy mass conservation. For this analysis, an iterative technique of successively approximating the zonal pressure is used. The results of applying this study model to several simple cases are as follows. When there is no wind and only the stack effect is caused, a one-way flow occurs in both the top and bottom openings in the case of two openings of equal-area, and a one-way flow occurs in the top opening; however, a two-way flow occurs in the bottom opening in the case of two openings of unequal-area. When there is a wind effect, regardless of whether the outside air temperature is lower or higher than the indoor air temperature, air flows into the room through the bottom opening and out of the room through the top opening. As the wind velocity increases, the wind effect appears to be more influential than the stack effect owing to the temperature difference.

Abstract
 1. 서 론
 2. 이론적 배경 및 연구방법
  2.1. 자연환기 모델의 이론적 해석
  2.2. 단일구획 빌딩에 대한 해석적인 이론
  2.3. 연구방법
 3. 결과 및 고찰
  3.1. 스택효과만 있는 경우의 자연환기량
  3.2. 풍속효과가 있는 경우의 자연환기량
 4. 결 론
 REFERENCES

• 조석호(부산가톨릭대학교 환경행정학과) | Seok-Ho Cho (Department of Environmental Administration, Catholic University of Pusan) Corresponding author