Why we need lossless CAD in CFD?

The Sub-Grid Geometry Resolution (SGGR) technology allows FlowVision to import the CAD file to the computational domain without any feature loss, thus both saving man hour for meshing and letting the engineer focus on the physics of the problem to be solved. SGGR technology helps preserving the curvilinear boundaries of the imported CAD geometry and other boundaries which may appear during the course of the calculation (such as free surfaces), even if the smallest cell size used in the calculation is not capable of resolving the curvature.

SGGR is a key merit to create high fidelity computational grid near the boundaries and achieve extremely high accuracy levels in VoF and FSI calculations. Combined with the locally adapted grid generation, importing a geometry and generating a high quality computational grid in FlowVision takes a few minutes.

For multi phase calculations, SGGR allows FlowVision to be able to specify boundary conditions (such as surface tension) on the real phase boundaries.

Numerical loses of water mass is avoided by SGGR in VoF calculations.
Together with Abaqus (Dassault Systèmes), FlowVision is the best tool to design against aquaplaning.

The Living Heart Project: Extremely accurate strongly coupled FSI simulations of a Human Heart with FlowVision-Abaqus.

Effect of SGGR on Other Capabilities

The unique SGGR technology enhances the fluid-body interface resolution capacity. Thanks to this; a smooth, lossless data transfer between Finite Element Analysis (FEA) tools and FlowVision can be established, paving the way to the ultimate accuracy for Fluid Structure Interaction (FSI). Through these sub-micron level resolution and strictly conservative data exchange capabilities, the state of art FSI calculations such as simulation of a beating human heart can be fulfilled.

Likewise, for Volume of Fluid (VOF) calculations SGGR helps to resolve and reconstruct the free surface topology even at a sub-grid level.

SGGR does not only allow seamless working of locally adapted Cartesian grid; together with unique FlowVision Gap Model and features such as user defined auto-offsetting, it also provides highly accurate solutions for calculations where hundreds of different parts are closely situated (e.g. micron level gaps in a cell phone cooling simulation).

Moreover, the CAD geometries can be replaced during the course of calculation without any manual grid regeneration efforts. Upon a geometry replacement, FlowVision strictly maintains the originally obtained mesh quality. This novel capability of offers a time-effective approach for optimization studies. Additionally, for multi-domain nonlinear automatized optimization, FlowVision can be coupled with 3rd party optimization tools such as IOSO.