General isotropic micropolar fluid model in smoothed particle hydrodynamics.

Area of Science:

• Computational Fluid Dynamics
• Non-Newtonian Fluid Mechanics
• Particle-Based Modeling

Background:

• Micropolar fluids exhibit complex behaviors due to microstructural elements and spin.
• Modeling these fluids requires capturing both velocity and spin dynamics.
• Existing methods may not fully address the intrinsic dissipation mechanisms in micropolar fluids.

Purpose of the Study:

• To develop and validate a smoothed particle hydrodynamics (SPH) model for micropolar fluids.
• To incorporate particle-level dissipation mechanisms, including spin effects.
• To achieve a general and accurate computational framework for micropolar fluid dynamics.

Main Methods:

• Utilized the smoothed particle hydrodynamics (SPH) method for fluid dynamics simulation.
• Defined a particle-level dissipation function dependent on relative velocity and spin.
• Incorporated the dissipation function into the Lagrangian formalism to derive SPH equations.
• Developed a continuous integral SPH version for enhanced term consistency.
• Enriched the model with spin derivative terms for maximal isotropic generality.

Main Results:

• The developed SPH model successfully incorporates spin degrees of freedom and associated dissipation.
• The model accurately represents the interplay between velocity and spin dynamics in micropolar fluids.
• Numerical verification and validation tests confirm the model's capability in simulating micropolar fluid dynamics.

Conclusions:

• Smoothed particle hydrodynamics (SPH) is a suitable and accurate method for modeling micropolar fluids.
• The inclusion of spin-dependent dissipation mechanisms enhances the fidelity of fluid simulations.
• The proposed model offers a generalized and computationally robust approach for studying micropolar fluid phenomena.