flow5 is a potential flow solver with built-in pre- and post- processing functionalities. Its purpose is to make the preliminary designs of wings, planes, hydrofoils and sails reliable, fast and user-friendly.

It is version 7 of the legacy project xflr5.

• Fix bugs and implement minor improvements depending on user requests
• Add fuselage conforming mesh capability to flow5-lib and to the API
• Remove the dependency of flow5-lib on Qt6-core
• Add plane imports from STL or OBJ meshes to the API
• Add fuselage imports from STL or OBJ meshes to the API
• Add fuselage imports from STEP files to the API
• Clarify the sign conventions used for the output of moments; see discussion #62.
• Either complete or remove currently inoperative features, e.g. plane optimization, advanced editors
• Continue to clean the code and to improve the API
• Clean the documentation

Please note that the API is still in an experimental state and subject to change.

The intent is to stabilize both the source code and the API by the end of 2026.

Even though the main part of the intended refactoring will have been completed with v7.57, deprecation or even discontinuation of interfaces are still likely until the end of the year.

• XFoilRun: Construction of a NACA foil and calculation of a type 1 polar using XFoil.
• XFoilBatchRun: Construction of a NACA foil and multi-threaded calculation of a 2d polar mesh.
• PlaneRun1: Construction of an xfl-type plane with no fuselage and calculation of a type 2 polar with viscous drag evaluated on the fly. Shows how to use custom units.
• PlaneRun2: Construction of an xfl-type plane with a NURBS type fuselage, construction of a conforming mesh, and calculation of a type 2 polar.
• PlaneRun3: Import of an stl-type plane from a mesh file, configuration of the trailing edge and calculation of a type 1 polar.
• PlaneRun4: Import of a plane and a polar from xml files, construction of a conforming mesh, and calculation of a type 1 polar.
• PlaneRun5: Import of an STL-type fuselage into an xfl-type plane.
• PlaneRun6: Import of a fuselage from a STEP file into an xfl-type plane.