We introduce a novel moving-mesh method with interface-tracking, designed to enable large and complex domain deformations, including topological changes. The (higher-order) meshing and re-meshing approach is based on block-structures. Therefore, the domain is coarsely partitioned into blocks, which are coarse, linear quads and each block may be meshed individually [2]. During a simulation, where the domain undergoes large changes, different block-structures are used, each tailored to represent a characteristic stage of the moving domain. The exact geometry and grading information is assigned to the block edges. This allows the generation of meshes of any order and spatial resolution with exact geometry information at all time steps during a simulation. A key part of the approach is the change between the block-structures which also influences the treatment of the governing equations. At these instances in time, data projection between the computational meshes is required. This task may be accelerated by using optimized search algorithms, such as bounding boxes, nevertheless, this is done rarely. This approach has been thoroughly tested for two-dimensional incompressible flow simulations including large translations and rotations, such as the flow through a rotary lobe pump or moving flaps in a channel flow [1]. The conceptual extension to three-dimensional problems is straightforward. Naturally, these simulations are more complex and computationally demanding. Additionally, the mesh generation is inherently more complex in three-dimensions and more advanced techniques for the generation of the different block-structures during a simulation are highly beneficial. The proposed concept supports large deformations, including topological changes throughout the simulation. Meshes of arbitrary order and resolution may be generated and may even be adapted to specific solution features, leading to a robust interface-tracking method. REFERENCES [1] T. Schalk, T.-P. Fries, Space-Time Block-structured Meshing in Coupled Problems with Moving Domains, Proc. Appl. Math. Mech., submitted, 2025. [2] T. Schwentner and T.-P. Fries, Fully coupled, higher-order, block-structured mesh generation in fluid-structure interaction, Int J Numer Meth Fluids., 97, 359–377, 2024.