ESTIMATION OF FLUID RESISTANCE OF RIVERINE WOODY COMMUNITIES BASING ON VELOCITY MESUREMENTS OF NATURAL WIND

The aim of this research is to develop a practical method for estimating fluid-resistance parameters, such as the resisting area per unit volume of the flow field, λ, and the representative drag coefficient, CD, of a riverine woody-plant community by using wind velocity data. Field observation of wind velocity was carried out with respect to boundary layers affected by a woody-plant community existing on a gravel bar formed in a downstream reach of the Yoshino River, in Tokushima Pref., Japan. From wind velocity measurements, six sets of velocity profile data were collected to be used for estimation of the fluid-resistance parameters. A two-dimensional k-e turbulent flow model was revised and successfully applied for estimating distribution of the product of the two fluid-resistance parameters, CDλ