flow5 makes use of the following libraries and technology:

The Qt libraries are the main building blocks of the application’s UI. It should be noted that the quality of the Qt libraries and Qt’s commitment to support open source development have been a formidable aid in making xflr5 and flow5 what they are today.

flow5 makes use of Intel’s Math Kernel Library (MKL), which is a library of optimized math routines for science, engineering, and financial applications. It contains core math functions including BLAS, LAPACK, ScaLAPACK, sparse solvers, fast Fourier transforms, and vector math. The routines in MKL are hand-optimized specifically for Intel processors. The library supports Intel processors and is available for Windows, Linux and macOS operating systems.

The use of MKL has helped reduce the analysis times by a huge factor. See this report (link) and this video (link) to learn more about the benefits.

Open Cascade Technology (OCCT) is an open-source software development platform for 3D CAD, CAM, CAE, etc. that is developed and supported by Open Cascade SAS.

OCCT libraries are used to construct wing-fuselage intersections. They are also used in flow5 for import and export operations in STL and STEP formats.