Determination of stage discharge curve for laboratory and river compound channels applying genetic algorithm

Many approaches with different assumptions have been developed for designing compound channels and prediction of their stage-discharge curves. Most of these methods have satisfactory results in laboratory compound flumes but extending them to all hydraulic and geometric conditions such as natural rivers is very limited. In this study, using nearly 400 laboratory and field stage-discharge data sets of 30 compound channels with different geometric and hydraulic conditions, a new method has been presented for calculation of flow discharge in compound channels, based on Genetic Algorithm. This proposed stage-discharge relation with sufficient accuracy (R2=0.91, MSE=0.01) in comparison with divided channel method (R2=0.27, MSE=0.11) can be used for all types of compound channels (laboratory and field). Therefore, this approach is suitably applicable in flood control projects, river flood routing and design of conveyance canals.