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Adaptive Mesh Refinement for Two-Phase Viscoelastic Fluid Mixture Models
Bindi M Nagda1, Aaron Barrett2, Boyce E Griffith3,4
1Department of Mathematical Sciences, Florida Institute of Technology, Melbourne, FL, USA.
Summary
This study introduces an adaptive mesh refinement (AMR) technique for simulating multiphase flows. The new method accurately captures fluid dynamics while significantly reducing computational costs.
Area of Science:
- Computational fluid dynamics
- Multiphase flow modeling
- Numerical analysis
Background:
- Multiphase flows are crucial in industrial, natural, and biomedical systems.
- Simulating these flows presents numerical challenges due to non-linear terms and co-incompressibility.
- Accurate simulation requires methods that handle high stresses and material gradients efficiently.
Purpose of the Study:
- To develop an adaptive mesh refinement (AMR) technique for simulating multiphase flow mixtures.
- To create an accurate, robust, and efficient computational method for adaptive grids.
- To address the numerical challenges in multiphase flow simulations.
Main Methods:
- Utilized a continuum model with separate momentum equations for each phase.
- Implemented an adaptive mesh refinement (AMR) technique.
- Employed a multigrid solver to precondition the saddle-point system.
Main Results:
- The AMR discretization achieves second-order accuracy in L1, L2, and L-infinity norms.
- The solver accurately resolves sharp gradients in the solution.
- Linear solver iterations are independent of grid spacing due to multigrid preconditioning.
Conclusions:
- The developed AMR solver provides significant cost savings, offering up to a ten-fold speedup over uniform grids.
- This method enhances the efficiency and accuracy of multiphase flow simulations.
- The technique is applicable to diverse industrial, natural, and biomedical systems.
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