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      Cart3D v1.4  (click here for v1.3 release)

What is Cart3D?  click here to see more examples
click on "Images" for more examplesCart3D is a high-fidelity inviscid analysis package for conceptual and preliminary aerodynamic design. It allows users to perform automated CFD analysis on complex geometry. The package includes utilities for geometry import, surface modeling and intersection, mesh generation, flow simulation and post-processing of results. The main simulation code,  flowCart, runs in parallel both in shared memory (OpenMP) and distributed memory (mpi) with excellent scalability. The package is highly automated so that geometry acquisition, and mesh generation can usually be performed within a few minutes on most current desktop computers.

Geometry enters into Cart3D in the form of surface triangulations. These may be generated from within a CAD packages, from legacy surface triangulations or from structured surface grids. Cart3D uses adaptively refined Cartesian grids to discretize the space surrounding a geometry and  cuts the geometry out of the set of "cut-cells" which actually intersect the surface triangulation. The flow solver is parallel and can take full advantage of multi-core and multi-cpu hardware.

The current release of Cart3D is v1.4, (the v1.3 webdocs are here). Version 1.4 has several major upgrades including significant solver improvements. Speed, robustness and flexibility have all been improved. We've added support for on-the-fly force and moment post-processing, and point and line sensors. The distribution also includes several new utility programs to help with process automation and now fully supports a 2D option, which is a great way to explore and test the package. There is also a new flowCart option that allows convergence to fixed lift (instead of angle-of-attack), to support experimental comparisons and design studies. There are significant improvements in robustness and performance across the board. Look here for news on the v1.4 release.

Importantly, v1.4 adds support for the Cart3D Adjoint Adaptation module. This module uses adjoint-weighted residual error-estimates to drive mesh adaptation. Once a user specifies outputs of interest, (lift, drag, etc.) with a corresponding error tolerance, this module automatically meshes the simulation to drive the remaining numerical errors in the outputs below the requested tolerance. Look here for details.

    What Platforms are Supported?

Currently supported platforms include Linux (X86_64, 2.6.32 or newer) and Mac OS-X (10.7 & 10.8). For information on other platforms, contact us.

   Cart3D HowTo's, images, publications, surface modeling, adjoint-based mesh adaptation geometry intersection
 mesh generation, flowCart, file formats, geometry import triangle formats, input/output files
boolean polytope intersection , adaptive precision floating point arithmetic, algorithmic tie-breaking

Michael AftosmisMarsha Berger,  Marian Nemec, John Melton

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last update June, 2013, M. Aftosmis