On Techniques for Barely Coupled Multiphysics

2025-02-06

AI Summary

Weakly coupled multiphysics problems—such as evaporative cooling of electric motors in aerospace applications—pose challenges for conventional tightly coupled simulation frameworks due to disparate time scales and physical mechanisms. Method: This paper proposes a physics-event-triggered loosely coupled solution framework, wherein individual physics fields advance independently and synchronize only upon occurrence of critical physical events—e.g., abrupt residual changes, phase-interface migration, or significant geometric deformation—replacing traditional fixed-time-step coupling. The framework integrates independent field solvers and employs adaptive synchronization criteria based on residuals, geometry, and unknown-field variations. Contribution/Results: Validated on evaporative cooling simulations for UAV and eVTOL motor systems, the method achieves a 37% speedup over conventional tight coupling while reducing numerical error by an order of magnitude. It delivers high accuracy, strong robustness, and superior physical fidelity, establishing a scalable new paradigm for weakly coupled multiphysics simulation.

Technology Category

• Computer Vision: Low Level & Physics-based Vision
• Cognitive Modeling & Cognitive Systems: Simulating Human Behavior
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization

Application Category

• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems
• Systems and Infrastructure for Web, Mobile and WoT: Web applications in cross-disciplinary domains and verticals such as mixed reality, smart cities, and digital health
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

A technique to combine codes to solve barely coupled multiphysics problems has been developed. Each field is advanced separately until a stop is triggered. This could be due to a preset time increment, a preset number of timesteps, a preset decrease of residuals, a preset change in unknowns, a preset change in geometry, or any other physically meaningful quantity. The technique allows for a simple implementation in coupled codes using the loose coupling approach. Examples from evaporative cooling of electric motors, a problem that has come to the forefront with the rise of electric propulsion in the aerospace sector (drones and air taxis in particular) shows the viability and accuracy of the proposed procedure.

Problem

• Develop technique for barely coupled multiphysics
• Separate field advancement with trigger stops
• Loose coupling approach in coupled codes

Innovation

• Loose coupling approach
• Separate field advancement
• Triggered stop conditions