Applications of a novel wall-modeled large-eddy simulation approach combined with the immersed boundary method for studying turbulent flows through complex geometries

The study of turbulent flows and their interaction with geometrically complex objects remains a major challenge in engineering, particularly in the aerospace field. Accurate representation of the geometry, generation of computational meshes capable of resolving the flow field, and modeling of the near-wall region are key issues that must be addressed. A representative aerospace example is the flow over a wing with deployed high-lift devices, such as flaps or slats, where intricate interstitial flows develop within the cavities formed between components. These configurations involve strong turbulence, separation, and complex boundary conditions that are difficult to simulate accurately with traditional approaches. In this context, the present thesis aims to develop a novel numerical tool for Wall-Modeled Large Eddy Simulations (WMLES) of turbulent flows over geometrically complex boundaries. The work is based on the open-source code CaNS (Canonical Navier-Stokes), which has been modified to support WMLES. Key additions include a Signed Distance Field (SDF), enabling the detection of arbitrary immersed geometries, and an Immersed Boundary Method (IBM) for the automated enforcement of boundary conditions on solid surfaces. The accuracy of the implementation is verified through two test cases: a turbulent channel flow and a pipe flow. As a final application, the solver is used to simulate the flow around three more complex geometries, to test the code under different operative conditions.