Statistical-learning method for predicting hydrodynamic drag, lift, and pitching torque on spheroidal particles.
S Tajfirooz1, J G Meijer1, J G M Kuerten1
1Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB, Eindhoven, The Netherlands.
Physical Review. E
|March 19, 2021
Summary
A new neural network model accurately predicts hydrodynamic forces on particles, outperforming traditional methods. This statistical learning approach enhances simulations of particle motion in fluids.
Area of Science:
- Fluid dynamics
- Computational science
- Statistical learning
Background:
- Predicting hydrodynamic interactions of non-spherical particles is complex.
- Existing empirical correlations have limitations in high-dimensional input spaces.
Purpose of the Study:
- To develop a statistical learning approach for predicting hydrodynamic interactions of thin oblate spheroidal particles.
- To replace conventional empirical correlations with a more accurate neural-network-based model.
Main Methods:
- Performed resolved simulations of steady uniform flow around a 1:10 spheroidal body (1 ≤ Re ≤ 120).
- Collected a database of Reynolds number- and orientation-dependent drag, lift, and pitching torque.
- Trained and validated a multilayer perceptron using the generated database.
Main Results:
- The neural network accurately predicts hydrodynamic forces (drag, lift, torque).
- The statistical approach shows higher accuracy than existing empirical correlations.
- Simulations of buoyancy-driven disk motion using the model show good agreement with experimental data.
Conclusions:
- The neural network-based statistical learning approach offers a more accurate prediction of hydrodynamic interactions.
- This method has significant potential for improving particle-resolved simulations, especially for non-spherical particles.
- The findings validate the method's effectiveness against experimental observations.
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