Tips & Tricks

Visual Display of Bad Cells in CFD-VisCART

Most models have certain parts or regions where the grid density needs to be higher than other areas to accommodate for steep curvatures, sharply changing topology, etc.

Handling Multiple holes for surface operations in CFD-GEOM

In the past, cutting or filling holes in surfaces with CFD-GEOM required a two step process; 1) pick the surface 2) pick the closed set of curves that forms the hole. Not a bad process but in the case of having to cut the surface with multiple holes, it was quite inefficient since you could only cut one hole at a time.

Edge Substitution for surfaces in CFD-GEOM

The Edge Substitution tool in CFD-GEOM is designed to make it easy to modify surface boundaries. It allows you to replace the lines/curve of a surface with edges, and vice versa.

Local Curve Meshing in CFD-GEOM

Computational geometries/assemblies often involve parts that may vary in scale. Although unstructured surface meshing adapts to the size of the geometry, in some cases there may not be sufficient grid density in specific regions of your model.

Digital Signal Processing using CFD-VIEW

Signals (stream of data) obtained from physical or numerical experiments often require additional processing to understand/interpret the physics they represent. The processing of signals through digital means is termed Digital Signal Processing (DSP).

Geometric Precision and Filtering in CFD-GEOM

In many cases, CAD models can be dirty and thus do not import well into CFD-GEOM. Repairing these geometries can often take considerable time and effort. Many times, duplicate points, lines, and surfaces are created when importing CAD geometries.

Using Local and Global Body Fit Factors in CFD-VisCART

The 'Body-fit Factor' is a percentage value used to determine how closely the Cartesian mesh front faces are projected to the real geometric surfaces. In other words, the Body-fit factor controls grid quality versus geometric fidelity. The value is between 0% and 100%, where 0%means no projection and 100% means complete projection to the surface.

Surface facet selection tool in CFD-VisCART

CFD-VisCART has always allowed surface selection where any surface can be selected by clicking on the graphics area or in the explorer window. Additionally, there is Facet Selection tool that allows the user to select individual facets or triangles of a surface (each surface is composed of triangulated faces called facets).

Plotting Multiple Variables in the CFD-VIEW Plotter

Plotting two or more variables on same plot having values of different magnitude/scale becomes difficult or many times impossible. In these cases plotting data with multiple Y-axes becomes very useful and sometimes necessary.

Low Mach Preconditioning and Dual Time Stepping in CFD-FASTRAN

Density-based schemes employing time-marching procedures available in CFD-FASTRAN provide excellent stability and convergence characteristics for high-speed compressible flows (typically M >0.5).