|13 Dec 2011
CNEMLIB is an implementation of CNEM in 2d and 3d ,. The CNEM is a generalisation for non convex domain of the Natural Element Method. The CNEM is a FEM like approach. The main advantages of the CNEM comparatively with the FEM, are the following:
- nodes and quadrature points are identical, all the unknowns (primal and dual unknowns introduced in Galerkin approaches) are attached to the nodes,
- due to the usage of Natural Neighbour Shape functions, the CNEM doesn't depend on mesh.
The main functionalities of CNEMLIB are:
i) interpolation of scattered data spread on convex or non convex domains with :
- in 2d, the Natural Neighbour interpolant (Sibson )
- in 3d, the Natural Neighbour interpolant (Sibson or Laplace) or the linear finite element interpolant over the Delaunay tessellation.
ii) a gradient matrix operator which allows to calculate nodal gradients for scattered data. The approach used is based on the stabilized nodal integration SCNI.
iii) a general assembling tools to construct assembled matrix associated with a weak formulation (heat problem, mechanic problem, hydrodynamic problem, general purpose problem) as such used with the Finite Element Method (FEM).
The functionalities i) and ii) are written in c++ and wrapped for matlab (mex function) and python(c++ extension). They are parallelised for 3d applications (shared memory using tbb). The assembling tools iii) are provided in matlab and python.
 L.Illoul,P.Lorong, On some aspects of the CNEM implementation in 3D in order to simulate high speed machining or shearing, Computers and Structures , Volume 89 Issue 11-12, June, 2011
 F.Chinesta, Natural Element Method for the Simulation of Structures and Processes, Wiley-ISTE; 1 edition (March 29, 2011)
 N. Sukumar, http://dilbert.engr.ucdavis.edu/~suku/nem/
 J.Chen, http://www.seas.ucla.edu/~jschen/2004%20SCNI%20for%20NEM.pdf
 H.Si, http://tetgen.berlios.de/