The University of Tokyo · 환경과학
홍연화 교수의 연구실은 대기경계층 및 도시 환경에서의 오염물질 확산 메커니즘을 해석하고자, 후방 추적 모델링 기반의 정량적 분석 기법을 개발하고 있습니다. 주로 도시지형의 복잡한 지형과 거칠기 특성에 기인한 농도 및 물질 교환 플럭스의 공간 분포 특성을 실험과 수치 시뮬레이션을 통해 규명하고 있으며, 특히 거칠기 하층 내에서의 센서 위치에 따른 피드백 분포의 이질성에 초점을 맞추고 있습니다. 이와 더불어, 보다 정확한 대기질산측정을 위한 기초 데이터베이스 구축과 수치 모델의 정합성 검증도 핵심 과제입니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
This study developed a backward-Eulerian footprint modelling method based on an adjoint equation for atmospheric boundary-layer flows. In the proposed method, the concentration footprint can be obtained directly by numerical simulation with the adjoint equation, and the flux footprints can be estimated using the adjoint concentration based on the gradient diffusion hypothesis. We first tested the proposed method by estimating the footprints for an ideal three-dimensional boundary layer with diff
Abstract This study addresses the need to investigate footprint function features in urban areas and establish a validation database for numerical methods. Concentration and its flux footprints of a block-arrayed urban model were measured in a wind tunnel with a neutrally stratified boundary layer. The velocity and concentration were simultaneously measured by an X-probe hot wire anemometer and a fast-response flame ionization detector to evaluate the vertical flux. Experimental results highligh
This study investigates the footprint distributions at various measurement positions in an urban array model, considering two incident wind directions, 22.5° and 45°, by a wind tunnel experiment. The airflow velocity and tracer concentration are simultaneously measured by an X-probe hot wire anemometer and a flame ionization detector, respectively, to assess the vertical flux of tracer gas. The experiment findings reveal a unified relationship between footprint distributions and measurement heig
Abstract This study addresses the need to investigate footprint function features in urban areas and establish a validation database for numerical methods. Concentration and its flux footprints of a block-arrayed urban model were measured in a wind tunnel with a neutrally stratified boundary layer. The velocity and concentration were simultaneously measured by an X-probe hot wire anemometer and a fast-response flame ionization detector to evaluate the vertical flux. Experimental results highligh
Abstract This study developed a backward-Eulerian footprint modeling method based on an adjoint equation for the urban environment, which has complex terrains and a high degree of heterogeneity. In the proposed method, the concentration footprint can be obtained directly by simulating the equation, and the flux footprints can be estimated using the adjoint concentration based on the gradient diffusion hypothesis. We first tested the proposed method by estimating the footprints for an ideal three
