Information Entropy Theory Applied to the Dip-Phenomenon Analysis in Open Channel Flows

Area of Science:

• Fluid Mechanics
• Hydraulic Engineering
• Open Channel Flow

Background:

• Accurate fluid discharge measurement in open channels is time-consuming and equipment-intensive.
• Existing models estimate mean velocity from maximum velocity, but the dip-phenomenon complicates prediction.
• The velocity-dip phenomenon, where maximum velocity is below the free surface due to secondary flows, poses a challenge in 3D open channels.

Purpose of the Study:

• To develop a novel mathematical model for predicting the velocity-dip position in open channels.
• To overcome limitations of existing methods in estimating maximum velocity location.
• To provide an accurate method for evaluating velocity distribution across the entire cross-section.

Main Methods:

• A mathematical model based on information entropy theory was developed.
• The model was designed to evaluate the velocity-dip-position across the full cross-section.
• The model's validity was tested using extensive literature measurement sets from uniform and non-uniform flows.

Main Results:

• The proposed model accurately estimates the velocity-dip-position in both wide and narrow open channels.
• The model demonstrated good agreement with experimental data from various flow conditions.
• It provides a reliable method for predicting the location of maximum velocity.

Conclusions:

• The information entropy-based model effectively addresses the challenge of predicting velocity-dip position.
• This approach simplifies the estimation of fluid discharge by accurately locating maximum velocity.
• The model offers a valuable tool for hydraulic engineers and researchers studying open channel flows.