FinEtoolsFlexStructures.jl

FinEtools used for

Simulations of large-displacement response of three-dimensional flexible-beam structures. Linear static analysis, modal analysis, linear buckling analysis. Nonlinear statics and dynamics;
Simulations of shell structures. Linear static analysis, modal analysis, explicit dynamic analysis. Shells can be homogeneous or layered (laminated, composite).

Current limitations

Only elastic structures can be modeled.
Only simple solid or closed thin-walled beam cross sections are implemented. Open thin-walled beams cannot be simulated at this point since the warping of the section is not enabled.
Shell reference surface offset not yet tested.
Neither general beams nor shells can be attached with an offset (eccentricity). There is a linear beam model that can be used with eccentricities (offsets of the attachment points relative to the nodes).

News

05/27/2024: Fix documentation of test module.
02/25/2024: Update for FinEtools 8.

Tutorials

There are a number of tutorials explaining the use of this package. Check out the index. The are tutorials themselves can be executed as follows:

Download the package or clone it.

git clone https://github.com/PetrKryslUCSD/FinEtoolsFlexStructures.jl.git

Change into the tutorials folder: cd .\FinEtoolsFlexStructures.jl\tutorials.
Start Julia: julia.
Activate the environment:

using Pkg; Pkg.activate("."); Pkg.instantiate();

Execute the desired tutorial. Here we arbitrarily pick one:

include("circle_modal_tut.jl")

When running a tutorial with graphical plotting in VSCode, make sure to turn off (uncheck) "Julia: Use Plot Pane" in the Preferences. Otherwise the animations will not work.

Charts and such are plotted with Gnuplot. Please make sure you have that installed in such a place that Julia REPL can find it.

Examples

Let us assume that the working directory is "FinEtoolsFlexStructures.jl", perhaps as a result of cloning the repository.

The project needed for running examples can be activated and initialized by

using Pkg; Pkg.activate("./examples"); Pkg.instantiate();

There are a number of examples, which may be executed as described in the conceptual guide to [FinEtools] (https://github.com/PetrKryslUCSD/FinEtools.jl). As an example:

julia> include(".\\examples\\shells\\dynamics\\dcbs_vibration_examples.jl")                 
WARNING: replacing module dbcs_vibration_examples.             
[ Info: All examples may be executed with                      
using .Main.dbcs_vibration_examples; Main.dbcs_vibration_examples.allrun()       
                  
julia> using .Main.dbcs_vibration_examples; Main.dbcs_vibration_examples.allrun()                         
                  
#####################################################          
# test_convergence
[ Info: FV12 free vibration, formulation=FinEtoolsFlexStructures.FEMMShellT3FFModule                        
[ Info: Mesh: 1 elements per side
count(fens) = 143 
fs = [21.613635088738015, 29.23401281588026, 30.925491823018966, 34.36778956332975]                         
[ Info: Mesh: 2 elements per side   
count(fens) = 567 
fs = [20.569847475978634, 26.277349178877216, 30.027181006351178, 30.68607366768112]                        
[ Info: Mesh: 3 elements per side   
count(fens) = 2255
fs = [20.350441226155656, 25.67267626791537, 29.124064583761363, 30.620439988286456]                        
[ Info: Mesh: 4 elements per side   
count(fens) = 8991
fs = [20.301524870325565, 25.533290848730623, 28.914284995255777, 30.620822302876647]                       
true

There is usually some indication of what the correct answer should be in the document string of the module: refer to the Julia file defining the examples.

Visualization

This is possible with PlotlyJS.jl with the package VisualStructures. Static plots or animation of deformation during a static or dynamic simulation can be done.

Export to Paraview is also available. Static pictures and time collections (useful for animations) are supported this way.

Documentation

Paper on explicit dynamics accepted for publication in the International Journal for Numerical Methods in Engineering. Draft is available in PDF.
Paper describing the robust triangular flat-facet shell element has been accepted for publication in the International Journal for Numerical Methods in Engineering. Draft is available in PDF.

Past news

12/30/2023: Update for Julia 1.10.
12/21/2023: Tutorials merged back into the package tree.
09/26/2023: Multiple examples revised. Numerous documentation improvements.
08/14/2023: Updated for Julia 1.9.2. Revised nomenclature of layup transformation matrices.
07/13/2023: Updated for Julia 1.9 and FinEtools 7.
05/26/2022: Paper on explicit dynamics accepted for publication in the International Journal for Numerical Methods in Engineering. Draft is available in PDF.
05/07/2022: Upgraded to Julia 1.7.2.
02/13/2022: Paper describing the robust triangular flat-facet shell element has been accepted for publication in the International Journal for Numerical Methods in Engineering. Draft is available in PDF.
01/29/2022: Explicit dynamics with CSR sparse matrix parallel multiplication.
12/31/2021: Implemented model for layered (laminated, composite) plates and shells.
12/20/2021: Reorganized examples into a project.
12/14/2021: The shell element T3FF fully tested, and described in a paper (submitted).
08/18/2021: Implemented linear statics and dynamics of shells using the DSG triangle with various improvements. Robust and accurate element.
05/23/2021: Updated for Julia 1.6.
08/23/2020: Added a separate tutorial package, FinEtoolsFlexStructuresTutorials.jl).
08/16/2020: Described the tutorials.
07/27/2020: Added documentation.
02/25/2020: Beams: Nonlinear static analysis implemented.
02/20/2020: Beams: Nonlinear transient dynamic analysis implemented.
02/16/2020: Beams: Buckling analysis implemented.