Application of Flow Velocity Distribution Models to Channel Discharge Measurements

Mathematical models were developed at the Water Survey of Canada (WSC) for describing flow velocity distribution in cross-sections of natural channels, for both open channel flows and flows under ice cover. The models use two types of parameters to represent the site-specific characteristics of channel flows: the roughness parameters representing effects of channel bed and bottom surface of ice cover (if present) and the hydraulic parameter representing the effects of hydraulic slope and viscosity of the flow. The flow velocity distribution models were applied to the determination of discharges of natural channels in WSC's operations. The applications include: the establishment of discharge calculation scheme with flow velocity data generated by AFM (acoustic flow meter) installation; the development of an alternative winter flow monitoring system for discharge measurements; and the development of a procedure for establishing the stage-discharge relationship of a gauging station with limited amount of data of one or two field flow measurements.