Author(s): Alain Recking; Andre Paquier; Philippe Frey; Philippe Belleudy; Jean Yves Champagne
Linked Author(s): André Paquier, Philippe Frey, Alain Recking
Keywords: Flow resistance; High Slope; Bedload; Hydraulic experiment; Image analyses
Abstract: The main difficulty in estimating flow resistance in presence of bedload transport is to measure the average velocity of the flow. Indeed, as the solid discharge increases, the use of a point gauge becomes difficult, even impossible. This is especially true at high slopes (1 to 10% ) associated with high solid discharge. In this paper we present a new measurement technique based on image analyses. This method, inspired by the well known salt-velocity technique, appeared to be simple and reliable. Velocity measurements are used to investigate the flow resistance, and instead of considering dispersion of data around a unique logarithmic law, we propose an original slope dependent law.