Publications

Journal Article

MPhys: A Modular Multiphysics Library for Coupled Simulation and Adjoint Derivative Computation

authors

A. Yildirim, K. E. Jacobson, J. L. Anibal, B. K. Stanford, J. S. Gray, C. A. Mader, J. R. R. A. Martins, and G. J. Kennedy

journal

Structural and Multidisciplinary Optimization, 68(15), 2025

doi

10.1007/s00158-024-03900-0

The design of many engineering systems requires multiphysics simulations and can benefit from design optimization. Two key challenges in multidisciplinary design optimization (MDO) are coupling the models and computing analytic derivatives, which are required to solve optimization problems with many design variables. While existing multiphysics frameworks address the challenge of implementing coupled models, none of them compute analytic derivatives for large-scale simulations in a general way. The OpenMDAO framework computes coupled derivatives using analytic methods, but it lacks suitable interfaces for simulation-based coupled models. To address this gap, we introduce MPhys, a modular multiphysics simulation library built with the OpenMDAO framework. MPhys defines standard disciplinary interfaces for coupled multidisciplinary models, enabling the rapid development of coupled multiphysics models for gradient-based MDO. We demonstrate MPhys’s modularity and extensibility with two example applications: aerostructural design optimization using two different aerodynamic solvers and aeropropulsive design optimization. Since its initial development, MPhys has been successfully used with a wide range of applications with various multidisciplinary coupling strategies and fidelity levels. The MPhys library is poised to significantly accelerate the integration of existing models in multiphysics applications and the development of new multidisciplinary coupling strategies. These developments will enable a wider adoption of MDO in practical engineering design.