Wind Tunnel Measurement of Aerodynamic Properties of a Tomato Canopy

Abstract

This study was conducted to determine the drag coefficient and the relationship between permeability (K) and momentum loss coefficients (Cf) of a tomato canopy for various leaf area densities. The experiments were conducted in a large-scale wind tunnel system with a tomato canopy. The static pressures and air velocity measurements were performed at several heights in the y-direction and various positions in the z-direction in the wind tunnel test section. The relationship between pressure drop and air velocity across the tomato canopy was determined using a porous medium approach. A drag coefficient of 0.31 was obtained for the tomato canopy used in the experiment. The permeability of the tomato canopy ranged from 0.006 to 0.65 for a leaf area density (L) of 4 (m2 m-3), from 0.004 to 0.41 for L = 5, and from 0.003 to 0.3 for L = 6 as Cf changed from 0.1 to 1. Thus, a mature tomato canopy having L = 6 could be used with a canopy permeability of K = 0.017 and a momentum loss coefficient of Cf = 0.245.