Structural-Optimisation

STSTOP Project - Hanger

Running the Project

Command to run the files:

# Generate mesh files with different resolutions
python 3dhanger.py --res <10,50,100>

Run the command with different values separately to generate three mesh files of different resolutions.

# Run the resolution script
python 3dhanger_run_res.py

Important: Make sure you run these commands in CMD and not PowerShell, as OpenCFS is not supported in PowerShell.

Installation Guide

Installing OpenCFS

Windows

1. Download the OpenCFS software from the official website
2. Install to the root of your user directory: C:\Users\<me>\openCFS
3. Add the following environment variables:
   • PYTHONPATH with value C:\Users\<me>\openCFS\share\python
   • CFS with value C:\Users\<me>\openCFS\share\python
   • CFS_QUIET with value 1
4. Add C:\Users\<me>\bin to your PATH
5. Create a directory bin in your user home and add the .bat files from "Windows .bat files"
6. Install Python 3.12 from https://www.python.org/downloads/ (Note: This specific version works better than Anaconda)
7. Ensure Python is in your PATH by testing in cmd: python --version
8. Install required packages:

   pip install numpy matplotlib h5py lxml Pillow scipy vtk

   (Note: scipy and vtk are not critical)

Testing the Installation

• Test Python: Run create_mesh --res 20 --type bulk2d in cmd
• Test OpenCFS: Run cfs --version in cmd

macOS

If you encounter an error during installation:

1. Go to System Settings → Privacy and Security
2. Scroll down to the "Security" heading and click "Open Anyway" to override Apple's security block

Installation steps:

1. Install Homebrew from https://brew.sh/
2. Unpack OpenCFS to /Users/<ME>/openCFS
3. Edit the hidden .zshrc file and add the following lines:

   export PATH=$PATH:$HOME/openCFS/bin:$HOME/openCFS/share/python
   export PYTHONPATH=$PYTHONPATH:$HOME/openCFS/share/python
   export CFS_QUIET=1

4. Install the required Python packages as listed in the Windows section

Installing Paraview

Download and install the latest version of Paraview from https://www.paraview.org/download/

Running CFS

Command Line Options

Get the available options via cfs --help. You are encouraged to experiment with these options.

Example commands:

• Basic simulation: cfs -m cantilever2d_20.mesh mech2d_cholmod

  • This looks for mech2d_cholmod.xml as the problem file
  • Output files will start with mech2d_cholmod

• To keep result files for comparison: cfs -m cantilever2d_20.mesh -p mech2d_cholmod.xml problem

  • Output files will start with problem

• To visualize a mesh file: cfs -g -m cantilever2d_20.mesh mech2d_cholmod

  • Generates a .cfs output file with mesh visualization
  • Skips the simulation (the settings in the <pde> section of the problem xml file are not read)

Saving Disk Space

CFS++ may generate large output files, especially when performing optimization and parameter studies. To save disk space:

1. In the simulation part in <storeResults>:
   • Have no region output in <nodeResult> and <elemResult>
2. Remove the HDF5 output writer
3. In the optimization part, use a large stride for <commit>, e.g., 9999