Journal of the Korean earth science society (한국지구과학회지)

The Korean Earth Science Society (한국지구과학회)
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The Verification of a Numerical Simulation of Urban area Flow and Thermal Environment Using Computational Fluid Dynamics Model

전산 유체 역학 모델을 이용한 도시지역 흐름 및 열 환경 수치모의 검증

  • Kim, Do-Hyoung (Applied Meteorology Research Division, National Institute of Meteorological Sciences) ;
  • Kim, Geun-Hoi (Applied Meteorology Research Division, National Institute of Meteorological Sciences) ;
  • Byon, Jae-Young (Applied Meteorology Research Division, National Institute of Meteorological Sciences) ;
  • Kim, Baek-Jo (Applied Meteorology Research Division, National Institute of Meteorological Sciences) ;
  • Kim, Jae-Jin (Department of Environmental Atmospheric Sciences, Pukyong National University)
  • 김도형 (국립기상과학원 응용기상연구과) ;
  • 김근회 (국립기상과학원 응용기상연구과) ;
  • 변재영 (국립기상과학원 응용기상연구과) ;
  • 김백조 (국립기상과학원 응용기상연구과) ;
  • 김재진 (부경대학교 환경대기과학과)
  • Received : 2017.09.13
  • Accepted : 2017.12.18
  • Published : 2017.12.31
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Abstract

The purpose of this study is to verify urban flow and thermal environment by using the simulated Computational Fluid Dynamics (CFD) model in the area of Gangnam Seonjeongneung, and then to compare the CFD model simulation results with that of Seonjeongneung-monitoring networks observation data. The CFD model is developed through the collaborative research project between National Institute of Meteorological Sciences and Seoul National University (CFD_NIMR_SNU). The CFD_NIMR_SNU model is simulated using Korea Meteorological Administration (KMA) Local Data Assimilation Prediction System (LDAPS) wind and potential temperature as initial and boundary conditions from August 4-6, 2015, and that is improved to consider vegetation effect and surface temperature. It is noticed that the Root Mean Square Error (RMSE) of wind speed decreases from 1.06 to $0.62m\;s^{-1}$ by vegetation effect over the Seonjeongneung area. Although the wind speed is overestimated, RMSE of wind speed decreased in the CFD_NIMR_SNU than LDAPS. The temperature forecast tends to underestimate in the LDAPS, while it is improved by CFD_NIMR_SNU. This study shows that the CFD model can provide detailed and accurate thermal and urban area flow information over the complex urban region. It will contribute to analyze urban environment and planning.

이 연구의 목적은 강남 선정릉지역에서 전산유체역학모델(CFD)을 사용하여 도시지역의 흐름 및 열 환경 모의를 검증하는 것이고, CFD 모델의 모의결과와 선정릉 지역의 관측 자료와 비교하는 것이다. CFD 모델은 국립기상과학원과 서울대가 공동으로 연구 개발된 모델이다. CFD_NIMR_SNU 모델은 기상청 현업 모델인 국지예보모델(LDAPS)의 바람성분과 온도성분을 초기 및 경계조건으로 적용되었고 수목효과와 지표 온도를 고려하여 2015년 8월 4일에서 6일까지 강남 선정릉 지역을 대상으로 수치실험을 진행하였다. 선정릉지역에서 수목효과 적용 전후의 풍속을 비교하였을 때 평균 제곱근 오차(RMSE)는 각각 1.06, $0.62m\;s^{-1}$로 나타났고 수목효과 적용으로 풍속 모의정확도가 향상되었다. 기온은 LDAPS 과소 모의하는 경향을 나타내고 CFD_NIMR_SNU 모델에 의해 향상된 것을 확인하였다. CFD_NIMR_SNU 모델을 이용하여 복잡한 도시지역의 흐름과 열 환경을 자세하고 정밀한 분석이 가능하며, 도시 환경 및 계획에 대한 정보를 제공 할 수 있을 것이다.

Keywords

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