/LCEFE

Liquid Crystal Elastomer Finite Element Simulation

Primary LanguageC++

Liquid Crystal Elastomer Finite Element

GPU accelerated finite element based electrodynamics simulation.

Written for research at Liquid Crystal Institute @ Kent State University, Kent OH

Authers:

** Andrew Konya ** Michael Varga

Building

  • Build using make
  • This compiles all object files and links to executable in builds/.
  • The name of the build is set by $(BUILDNAME) found on the first like of makefile

Runtime Parameters

  • The executable takes cmdline arguments to set parameters in the simulation. It also accepts a parameters file to read the values from.
  • An example parameters file params.json is provided. It reads standard json or the simplified json found in the example.
  • A list of available cmdline options and parameters are shown below...

Material Parameters

{name} : {type} : {description}

density : float : Sets the material density of the elastomer

alpha : float : Sets the compling stength of nematic order to stress

cxxxx : float : Primary elastic constant

cxxyy : float : Secondary elastic constant

cxyxy : float : Elastic constant

Simulation Parameters

{name} : {type} : {description}

nsteps : int : The number of timesteps to run the simulation

dt : float : The length of time steps

framerate : int : how often to print output files

Files to be aware of

classstruct.h defines both TetArray and NodeArray classes which are used to optimize the mesh on the CPU side.

getmesh.h parses the mesh (get_mesh), as well as optimizes the mesh ordering (gorder_tet).

packdata.h copies all mesh and initial condition data into arrays which can be coppied to the GPU

rundynamics.h handles the entire dynamics loop, including the invocation of the GPU side kernels.

gpuForce.h is the GPU side Kernel to handle force calculations, and uses:

  • forcecalc.h to do the actual force calculation
  • read_dev_data.h to get global GPU data needed for the force calculation
  • getQ.h is used to get the LC director for a given element
  • sendForce.h sends the forces calculated within the kernel to global memory

updateKernel.h is the GPU kernel to handle updating node positions and uses:

  • update_r.h to do the actual update equation calculations
  • sumForce.h is used to read and sum forces stored in global memory