Numerical Simulation of Flows around Broad-leaf Trees

Fuh-Min Fang; Yi-Chao Li; Cheng-Yang Chung

doi:10.6180/jase.2016.19.4.06

Numerical Simulation of Flows around Broad-leaf Trees

Fuh-Min Fang This email address is being protected from spambots. You need JavaScript enabled to view it.¹, 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, New Taipei City, Taiwan 231, R.O.C.

Received: January 6, 2016
Accepted: July 4, 2016
Publication Date: December 1, 2016

Download Citation: ||https://doi.org/10.6180/jase.2016.19.4.06

ABSTRACT

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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