CCARAT (Computer Aided Research Analysis Tool)

CCARAT is a research finite element program designed to solve a large range of problems in Computational Fluid and Solid Mechanics: e.g. multifield, multiscale and multidiscretisation schemes, shape and topology optimization problems and material modelling and element technology aspects. It is developed and maintained at the Institute of Structural Mechanics (IBS), University of Stuttgart and the Chair of Numerical Mechanics (LNM), Technical University of Munich. Various types of sophisticated structural elements (e.g. shell, brick and beam) and GLS stabilised fluid elements in 2d and 3d on a moving mesh (ALE formulation) are included in the code.

For the linear system of equations several external solvers (e.g. AZTEC, SPOOLES, UMFPACK and TRILINOS) as well as an in-house parallel semi-algebraic multilevel scheme based on the aggregation concept are available.

Fluid Structure Interaction

The considered class of Fluid Structure interaction applications falls under the category of transient interaction of incompressible viscous flows and nonlinear flexible structures. Partitioned analysis techniques enjoy more popularity than the fully coupled monolithic approaches, as they allow the independent use of suitable discretization methods for physically and/or dynamically different partitions. In this approach a non-overlapping partitioning is employed, where the physical fields (fluid and structure) are coupled at the interface, i.e the wetted structural surface. A third computational field, the deforming fluid mesh, is introduced through an Arbitrary Lagrangean-Eulerian description. Each individual field is solved by semi-discretization strategies with finite elements and implicit time stepping algorithms. The iterative substructuring schemes used are accelerated either analoque to a gradient method (method of steepest descent) or via an Aitken method.

Typical applications can be found in biomechanics, blood flow and aeroelasticity of structures like bridges and membrane structures.


Prof. Dr.-Ing. E. Ramm / Prof. Dr.-Ing. habil. Manfred Bischoff / Malte von Scheven
Institut für Baustatik und Baudynamik
Universität Stuttgart
Phone: ++49-711-685-66121
E-Mail: ramm/bischoff/

Prof. Dr.-Ing. W.A. Wall / Ulrich Kuettler
Lehrstuhl für Numerische Mechanik
Technische Universität München
Phone: +49-89-289-15238
E-Mail: wall/

Sunil Reddy Tiyyagura
Universität Stuttgart
Phone: ++49-711-685-65799