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Journal of Forestry Research

, 11:156 | Cite as

Wind tunnel experiment of drag of isolated tree models in surface boundary layer

  • Guan De-xin
  • Zhu Ting-yao
  • Han Shi-jie
Article

Abstract

For very sparse tree land individual tree was the basic element of interaction between atmosphere and the surface. Drag of isolated tree was preliminary aerodynamic index for analyzing the atmospheric boundary layer of this kind of surface. A simple pendulum method was designed and carried out in wind tunnel to measure drag of isolated tree models according to balance law of moment of force. The method was easy to conduct and with small error. The results showed that the drag and drag coefficient of isolated tree increased with decreasing of its permeability or porosity. Relationship between drag coefficient and permeability of isolated tree empirically was expressed by quadric curve.

Key words

Drag of isolated tree Wind tunnel experiments Pendulum method 

CLC number

S711 

Document code

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Copyright information

© Editorial Board of Journal of Forestry Research All right reserved 2000

Authors and Affiliations

  • Guan De-xin
    • 1
  • Zhu Ting-yao
    • 1
  • Han Shi-jie
    • 1
  1. 1.Institute of Applied EcologyChinese Academy of SciencesShenyangP.R. China

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