Overflow on Harold
OVERFLOW-D is a general purpose Navier-Stokes solver for problems that may involve relative motion between configuration components. The code uses overset structured grids to accommodate arbitrarily complex geometries while, on a component-wise basis, retain the computational advantages inherent to structured data.
OVERFLOW-D employs a powerful discretization paradigm that partitions the problem domain into near-body and off-body regions. The near-body region includes the surface geometry of all configuration parts being considered and the volume of space that extends a short distance above the respective surfaces. The near-body portion of the domain is discretized in a classical "Chimera' fashion. Near-body grids are generated in a pre-process using standard grid generation packages (OVERGRID is especially well suited to this task).
The off-body portion of the domain encompasses the near-body domain and extends to the far-field boundaries of the problem. OVERFLOW-D automatically discretizes the off-body domain with uniform Cartesian grid components (structured) of varying levels of resolution capacity. By default, off-body resolution capacity is set based on proximity to near-body components. Users can run simulations on the near-body and default off-body grid systems, or can enable solution adaption. With adaption enabled, OVERFLOW-D allocates off-body grid resolution based on proximity to near-body components and results of estimates of solution error. Of course, error estimation is carried out automatically by OVERFLOW-D. In all cases, OVERFLOW-D organizes grid components into groups of equal size. Then, on parallel computers, groups are assigned to processors. Scalability is realized in a group-wise fashion.
OVERFLOW-D can be used to simulate moving body applications that involve arbitrary rigid-body motion, prescribed motion, or maneuvers. OVERFLOW-D has a general 6-degrees-of-freedom model (6-DOF) that allows body motion to respond to aerodynamic loads as well as applied forces and moments associated with separation mechanisms. All OVERFLOW-D functionality is tightly coupled, including 6-DOF, domain connectivity, solution adaption, etc., in order to maximize computational efficiency for such applications.
OVERFLOW-D has the ability to restart calculations from information saved to files.
If you require help using this software, or would like to report a possible problem with it on one of our systems, please contact the Consolidated Customer Assistance Center.