General description

NDDEM is a full suit of tools to perform simulations and visualisions of granular media in any spatial dimension. This documentation gives information on the C++ code base, which has 3 modules. Dem is the N-dimensional simulation module, CoarseGraining performs coarse-graining of the data from the simulations, Texturing handles the rendering as UV maps of the orientation of the hyperspheres, and is designed to be used as an http server in conjunction with the Threejs visualisation module.

Program structure

DEM Examples

./DEMND 5 2006 in

: run the simulation with 5 dimensions, 2006 particles, based on the input file named in. Input file example are included in the source, and all commands are documented in the section Input script below.

Coarse-Graining Examples

./IONDDEM in

: run the simulation with 5 dimensions, 2006 particles, based on the input file named in. Input file example are included in the source, and all commands are documented in the section Input script below.

Texturing Examples

./TexturingServer

: Run the texturing server for calls from the visualisation side. Typical calling URL are available in the Texturing module.

Input script commands

Wall types

 boundary dim PBC low high

Periodic boundary condition between the boundaries at low and high.

 boundary dim WALL low high

Static walls at boundaries low and high (normal of the wall along the dimension dim).

 boundary dim MOVINGWALL low high vel_low vel_high

Walls moving along their normals

 boundary dim MOVINGSIDEWAYSWALL low high vel_low vel_high

Walls moving along their normals+1 dim

 boundary n SPHERE radius x1 x2 ... xn

Define a sherical wall. n should be higher than the dimension (walls or pbs should be defined in the other dimensions). (xi) is the location of the sphere centre.