Estimation of Flow Velocity Distribution in Smooth-Bed Open Channels with a Smooth Bed Using Entropy Theory and Genetic Programming

Document Type : Research Paper

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Abstract

Abstract
       With developing of entropy theory and genetic programming based on maximum entropy and natural evolution, respectively, these methods have been applied extensively to the variety of engineering sciences such as fluid mechanics and hydraulics. In this study, entropy, genetic programming and conventional methods such as logarithmic, power law and Vanoni relations were used for estimation water flow velocity distribution in open channels. For comparing the mentioned methods, experiments were carried out in an experimental flume with a smooth bed in the hydraulic laboratory of the University of Tabriz. The flow discharges ranged from 4.8 to 32.89 Lit/s. For each flow discharge, the vertical velocity profiles were prepared with a precision of 0.1 cm/s and at 1 cm intervals from the channel bottom. Results showed that entropy and genetic programming methods were more accurate than the other methods for estimating the velocity distribution. Moreover the entropy method in comparison with the genetic programming showed higher accuracy and therefore it could be used for estimating the velocity profiles with a good accuracy in open channel flows.

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