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Updated: May 16, 2026
10:52
Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
On efficient simulations of multiscale kinetic transport
Gregg A Radtke1, Jean-Philippe M Péraud, Nicolas G Hadjiconstantinou
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Summary
This study introduces novel multiscale kinetic simulation methods by decomposing problems into equilibrium and particle-based components. This approach significantly reduces computational cost for complex transport phenomena.
Area of Science:
- Computational Physics
- Chemical Engineering
- Materials Science
Background:
- Kinetic problems, especially those involving small-scale transport, present significant computational challenges.
- Existing simulation methods often struggle with the multiscale nature of these phenomena.
Purpose of the Study:
- To present a new class of adaptive approaches for simulating multiscale kinetic problems.
- To focus on applications relevant to small-scale transport phenomena.
Main Methods:
- Decomposition of the kinetic description into a deterministic equilibrium part and a particle simulation part.
- Derivation of evolution equations for both parts from the governing kinetic equation.
- Application of stochastic particle simulation methods with a control-variate variance-reduction formulation.
Main Results:
- A dynamically and automatically adaptive decomposition method is developed.
- The multiscale method seamlessly bridges deterministic and particle-based descriptions without approximation.
- Significant computational cost reduction is achieved for simulations of transport processes near equilibrium.
Conclusions:
- The proposed decomposition approaches offer substantial computational benefits for a wide range of applications.
- These methods enable otherwise intractable simulations by efficiently handling perturbations from equilibrium distributions.
- This work provides a powerful framework for simulating complex kinetic phenomena.
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