Journal of Applied Science and Engineering

Published by Tamkang University Press

ESCI jase impact factor scopus logo open access rate of Scopus journal

Numerical Simulation of Flows around Broad-leaf Trees

 2016

 Volume 19, Issue 4

Fuh-Min Fang1, Yi-Chao Li2 and Cheng-Yang Chung3

1Department of Civil Engineering, National Chung Hsing University, Taichung, Taiwan 402, R.O.C.

2Wind Engineering Research Center, Tamkang University, Tamsui, Taiwan 251, R.O.C.

3Architecture and Building Research Institute, Ministry of Interior, NewTaipei City, Taiwan 231, R.O.C.

Received: January 06, 2016
Accepted: July 04, 2016
Publication Date: August 02, 2026

上傳圖片

Sketch of experimental set-up.

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

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A numerical model was established to predict flow past discrete broad-leaf trees so as to provide a handy tool for pedestrian wind analysis during the preliminary design stage for local wind environments. In the study, a tree factor was proposed to reflect the effect due to the existence of the trees. Besides the applications of numerical computations in flow analysis, wind tunnel measurements were also performed to guide and confirm the numerical simulations. Results showed that the calibrated tree factor generally increased with increases of the volume ratio and horizontal thickness of the tree body. Based on the calibrated relationship of the tree factor, finally, additional numerical computations were performed to simulate flow past an isolated tree and dual trees in a tandem and a side-by-side arrangement. The predicted downstream wind velocity profiles appeared in good agreements with the measurement results.

Keywords: Large Eddy Simulation, Wind Tunnel Test, Bluff-body Flow, Porous Body

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