Turbulent flow through a random rigid submerged vegetation over a sinusoidal bed

Abstract

The present study investigates turbulent flow over a periodic small amplitude bed form with rigid submerged vegetation. The equations governing the flow are formulated using Biot’s poro-elasticity theory. Further, the Reynolds stress is modeled employing a linear term of the velocity gradient. Governing equations for vegetated and non-vegetated layers are non-dimensionalized and a perturbation parameter is identified. The leading order equation is solved employing power series method and first order equation is solved semi-analytically. The velocity components in the flow and transverse directions and the vertical shear stress distribution are evaluated. The velocity measurements are also carried out within the array over the perturbed bed using acoustic Doppler velocimeter. The experimental results are utilized to develop a correlation for the unknown coefficient present in the shear stress model, which is adopted for modelling the Reynolds stress.