A Code for 3D Topology Optimization of a Wheelset Structure with Orthotropic Constitutive Properties

===================================================================== A Code for 3D Topology Optimization of a Wheelset Structure with Orthotropic Constitutive Properties --------------------------------------------------------------------- Lee Alacoque, 2022 UIUC ===================================================================== This code is based on the framework written by Aage et al.: Aage, Niels, Erik Andreassen, and Boyan Stefanov Lazarov. "Topology optimization using PETSc: An easy-to-use, fully parallel, open source topology optimization framework." Structural and Multidisciplinary Optimization 51.3 (2015): 565-572. It requires the following to run: * PETSc * LAPACK/BLAS * MPI The code was written and tested on Ubuntu 20.04. It consists of a C++ program and a Matlab script for viewing and post-processing the output. To compile, set PETSC_DIR in the makefile to where your PETSc installation is, then type "make topopt" in the terminal. Run the code by typing e.g. "mpiexec -np 4 ./topopt". All input parameters are contained in the file "Inputs.cpp". After making any changes to the input values, recompile the code before running again. While running, the code writes output files of the results which can be viewed by running the Matlab script "ViewOutput.m". The script contains several control options for selecting which datasets to load and which post-processed output files to write. By setting the control option values to true, the script can write STL or VTK files for visualization in ParaView. ===================================================================== Description of files: main.cpp * The main program. It begins by creating class objects, the constructors of which perform the initializations for the topology optimization. It then moves into the optimization loop which runs by calling member functions from the class objects. When the optimization finishes, the program exits the loop and writes final output files before finalizing itself. Inputs.hpp & Inputs.cpp * Class containing input parameters for setting up the optimization. Mesh.hpp & Mesh.cpp * Class that sets up the finite element mesh. Opt.hpp & Opt.cpp * Class that sets up optimization parameters, contains functions for calculating various quantities of interest such as material volume and structural compliance, for objective and constraint functions, and for organizing the data to interface with the MMA optimizer functions. Projection.hpp & Projection.cpp * Class setting up variables and containing functions related to the super-Gaussian projection method for the variable loading and variable void region. Filter.hpp & Filter.cpp * Class for setting up and using the turning filter manufacturing constraint matrix. The filtering function also combines the projected void region with the filtered density field. FEA.hpp & FEA.cpp * Class which sets up the finite element model and contains the function for assembling the global load vector and stiffness matrix. The constructor of this class contains the code which sets up the boundary conditions of the problem. MMA.h & MMA.cc * The MMA optimizer class included in the original code by Aage et al. This updates the design in each optimization iteration based on sensitivity information calculated by the other classes. Outputs.hpp & Outputs.cpp * Class for writing the results of the optimization into output files. Functions.hpp & Functions.cpp * Files containing misc functions used throughout the program. makefile * The makefile containing the instructions for compiling the program. a.sbatch * The batch script file that was used to run the problem on the UIUC Campus Cluster. ViewOutput.m * MATLAB script that processes the output of the C++ program to immediately visualize some results, and/or further process it to create STL and VTK files. Top3dSTL_v3.m * MATLAB function used in ViewOutput.m to write the STL files. vtkwrite.m * MATLAB function used in ViewOutput.m to write the VTK files. "Results" Folder * This folder contains the raw results from the C++ program. ViewOutput.m can be used to generate the VTK files that the visualizations in the paper were made with. "VTK" Folder * The VTK files generated by ViewOutput.m, used to create the visualizations