ADflow: An Open-Source Computational Fluid Dynamics Solver for Aerodynamic and Multidisciplinary Optimization

Computational fluid dynamics through the solution of the Navier–Stokes equations with turbulence models has become commonplace. However, simply solving these equations is not sufficient to be able to perform efficient design optimization with a flow solver in the loop. This paper discusses the recommendations for developing a flow solver that is suitable for efficient aerodynamic and multidisciplinary design optimization. One of the major recommendations is to be able to load the flow solver as a library that provides direct memory access to the relevant data. Other recommendations are to use a higher-level language for scripting and to pay special attention to solution warm starting, code efficiency, flow solver robustness, and solution failure handling. As an example of a flow solver that follows these recommendations, the open-source flow solver ADflow is presented. Results from aerodynamic optimization, aerostructural analysis, and aerostructural optimization using ADflow demonstrate the performance advantages claimed in the recommendations. The publication of these recommendations and the availability of the source code open the door for other solvers to adopt the same application programming interface. ADflow is part of a wider aerodynamic shape optimization tool suite that is also available under an open-source license.