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An Entropic Model for the Assessment of Streamwise Velocity Dip in Wide Open Channels
Domenica Mirauda1, Marilena Pannone1, Annamaria De Vincenzo1
1School of Engineering, Basilicata University, Viale dell'Ateneo Lucano 10, 85100 Potenza, Italy.
Entropy (Basel, Switzerland)
|December 3, 2020
Summary
This study introduces a new theoretical model based on entropy theory to predict the velocity dip phenomenon in river flow. The model accurately forecasts the position and value of maximum velocity below the free surface, validated by field data.
Area of Science:
- Fluid Dynamics
- River Engineering
- Hydrology
Background:
- River flow exhibits complex three-dimensional structures.
- Secondary currents near walls cause maximum velocity to occur below the free surface (velocity dip).
Purpose of the Study:
- To develop a theoretical model for predicting the velocity dip phenomenon.
- To determine the position and velocity value of the maximum cross-sectional velocity.
Main Methods:
- A theoretical model derived from entropy theory was developed.
- The model's validity was tested using field data from the Alzette river (Luxembourg) and large rivers in Basilicata (Italy).
Main Results:
- The proposed model shows good agreement with experimental measurements.
- The model yields the least percentage error when compared to existing literature models.
Conclusions:
- The entropy theory-based model is effective for predicting river flow velocity dip.
- This model offers improved accuracy over existing methods for velocity dip prediction.
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