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Journal of Zhejiang University-SCIENCE A

, Volume 9, Issue 7, pp 907–915 | Cite as

Using FEM to predict tree motion in a wind field

  • Xiao-yi HuEmail author
  • Wei-ming Tao
  • Yi-mu Guo
Article

Abstract

In this paper we propose a finite element (FE) simulation method to predict tree motion in a wind field. Two FE tree models were investigated: One model was generated based on a realistic nature-looking geometric tree model, and the other was a symmetric model to investigate the influence of asymmetric material properties on tree motion. The vortex-induced vibration (VIV) theory is introduced to estimate the fluctuating wind force being exerted on tree stems and the fluid-structure interaction (FSI) analysis is also included in the simulation. The results indicate that asymmetric material properties result in the crosswind displacement of the investigated node and the main swaying direction deviation. The simulation reveals that under wind loading, a tree with leaves has much larger swaying amplitude along the wind direction and longer swaying period than a tree without leaves. However, the crosswind swaying amplitude is mainly due to branch interaction. The numerical simulation proved that the interaction of tree branches can prevent dangerous swaying motion developing.

Key words

Finite element method (FEM) Fluid-structure interaction (FSI) Vortex-induced vibration (VIV) Asymmetric Wind field 

CLC number

O39 O368 S7 

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Copyright information

© Zhejiang University and Springer-Verlag GmbH 2008

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringZhejiang UniversityHangzhouChina
  2. 2.School of EngineeringZhejiang Forestry UniversityHangzhouChina

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