Measuring and modeling flow structures in a small river

As part of a project to examine the feasibility of using new measurement techniques to evaluate the conveyance capacity of a small river, acoustic Doppler current profiling (ADCP) has been deployed on a 300m stretch of the river Blackwater, Hampshire, UK. This particular reach corresponds to a doubly meandering two stage channel with various complex cross sections. Velocity data are examined for a variety of flows in order to evaluate the flow structures which exist within the channel. The work has been undertaken over a three year period which allows the impact of changes in seasonal vegetation to be examined. Finally, the applicability of using a quasi 2-D RANS model (the SKM) to model the depth averaged streamwise velocity distribution is examined.