Professor Hrvoje Jasak gave a plenary talk entitled “Dancing meshes: Past and Present of Dynamic Mesh Support in OpenFOAM” at the 7th ESI OpenFOAM conference in Berlin, Germany. Find the summary of the talk and the presentation slides below.
The summary of the talk:
There exists a large and growing class of problems accessible to CFD which involve varying geometry of the computational domain, either in a prescribed manner (such as turbomachinery, volumetric pumps and compressors, screw extruders or internal combustion engines) or with solution dependent geometry (such as fluid-solid interaction, contact problems in solid mechanics and 6-DOF floating body problems in naval hydrodynamics). While mesh generation and dependence of the CFD solution on mesh structure and quality remains the most challenging aspect of modern CFD, a promising way forward includes solution-dependent automatic mesh refinement, which falls into the same class.
To handle such simulations, it is necessary to allow for the computational mesh to change during the simulation and preserve strong mass, momentum and energy conservation. Further, setup of such cases has historically been troublesome and finding the methods to set them up with ease is a significant challenge. I am delighted to state that all dynamic mesh capabilities described above, together with dynamic load balancing and other HPC support tools are taken for granted by today’s users of OpenFOAM, proving that this job has been successfully performed so far.
In this presentation, I will present my work on dynamic mesh support in OpenFOAM, from the early days of dynamic mesh refinement in 1993 to the latest Immersed Boundary Surface method in 2019. Having completed the first fully functional polyhedral mesh support in a CFD code, flexibility of such meshes is used as the basis of dynamic meshing. Starting with simple support for moving deforming mesh, the methodology has been developed to include automatic mesh deformation techniques using FVM and FEM solvers; adaptive mesh refinement based on split hex features; conventional sliding/layering dynamic mesh support, dynamic tetrahedral remeshing and has progressed to today’s state-of-the art features of dynamic Overset Mesh and Immersed Boundary surface. This presentation shall cover the methodology, examples of use and guidance on quality and applicability of various dynamic mesh methods to which I have contributed over the last 25 years.
Download slides here.