Diffusion in developing turbulent flow

The dispersion of matter in an open channel under conditions of steady, two dimensional, developing and fully developed flow is investigated. The method of approach used to predict heat and mass transfer in turbulent boundary layer, is extended to the solution of the problems of the diffusion of solid particles of finite sizes in open channel flows with different bed roughnesses. The momentum and diffusion equations are solved numerically utilizing a finite difference technique and a marching-integration procedure. The mathematical models used for the turbulent exchange coefficients are those involving the eddy viscosity and mixing length. Various combinations of boundary and other input conditions are imposed and their effect on the results is demonstrated. The solution procedure described is used to compare experimental data with calculated velocity and concentration distributions to demonstrate the capabilities of the method.