When an engineering consultant delivers analysis results, how do you know the calculations are correct? Traditional approaches rely on trust, credentials, and spot-checking sample calculations. Open-source engineering tools offer something better: complete transparency into the computational methods behind the results.
This article explores why open-source matters for engineering software, introduces our GitHub repositories for structural analysis and fatigue assessment, and explains how engineers can use and contribute to these tools. Whether you're evaluating engineering consultants or looking to improve your own computational workflows, understanding the open-source advantage is increasingly important.
Why Open-Source Matters in Engineering
Engineering software has traditionally been proprietary. Commercial FEA packages, fatigue analysis tools, and structural design software come as compiled binaries with closed source code. You input parameters, run the analysis, and receive results—but the actual calculations remain hidden in a black box.
This creates several problems:
- Validation challenges: How do you verify that a commercial tool correctly implements the equations in your design code? You can run benchmark problems, but you can't examine the implementation directly.
- Debugging difficulties: When results look suspicious, you can't trace through the calculation logic to find where things went wrong.
- Vendor lock-in: Your analysis workflows become dependent on specific commercial tools. Switching vendors means revalidating everything.
- Limited customization: If the tool doesn't support your specific use case, you're stuck waiting for the vendor to add features.
Open-source engineering tools address all of these issues. The source code is available for inspection, modification, and improvement. When you see suspicious results, you can trace the exact calculation path. When you need custom functionality, you can add it yourself.
The Trust Problem in Engineering Consulting
Consider the perspective of an engineering manager evaluating consultants for a critical offshore structure analysis. The consultant delivers a fatigue assessment report showing adequate design life. How do you evaluate the quality of that work?
Open-source methodologies change this dynamic. When a consultant uses open-source tools and publishes their calculation scripts, clients can:
- Review the exact algorithms used in the analysis
- Verify compliance with design codes and standards
- Run independent checks using the same methodology
- Identify assumptions and limitations in the analysis
- Reproduce results with different inputs for verification
This transparency doesn't replace engineering judgment—it enables it. When you can see exactly how a result was calculated, you can apply your own expertise to evaluate whether the approach is appropriate for your specific situation.
Our GitHub Organization
We maintain several open-source repositories for computational engineering on GitHub. These tools reflect our production methodologies—the same code we use for client projects is available for inspection and use.
fatigue-analysis
A Python library for fatigue life assessment of welded structures. Implements S-N curve methods per DNV-RP-C203, rainflow cycle counting, stress concentration factors for common joint types, and cumulative damage calculations using Miner's rule.
- Hot spot stress extraction from FEA results
- Rainflow counting for variable amplitude loading
- Multiple S-N curve options (DNV, BS, API)
- Thickness correction and environmental factors
- Automated report generation
fea-postprocessing
Tools for automating FEA post-processing workflows. Reads results from common formats (CSV exports from ANSYS, Abaqus, etc.), performs code checks, and generates structured output for reporting.
- Multi-format result file parsing
- Automated stress categorization (membrane, bending, peak)
- Code compliance checking (API, ASME, DNV)
- Interactive visualization with Plotly
- Batch processing for parameter studies
engineering-calcs
A collection of validated engineering calculations for common structural problems. Each calculation includes derivation references, validation against hand calculations or published examples, and unit tests.
- Beam and plate stress calculations
- Pressure vessel formulas (ASME Section VIII)
- Connection design checks
- Marine structure calculations (hydrostatics, stability)
- Environmental loading (wind, wave, current)
Open-Source vs. Proprietary: A Comparison
Let's compare open-source and proprietary approaches across several dimensions that matter for engineering work:
| Criterion | Proprietary Software | Open-Source Tools |
|---|---|---|
| Transparency | Black box calculations | Full source code visibility |
| Validation | Trust vendor testing | Review implementation directly |
| Customization | Limited to vendor features | Modify for specific needs |
| Cost | License fees (often $10K+/year) | Free (development time investment) |
| Support | Vendor helpdesk | Community + consultants |
| Longevity | Depends on vendor viability | Code persists indefinitely |
| Integration | Often limited APIs | Full programmatic access |
How to Use Our Tools
Getting started with our engineering tools requires basic Python knowledge. Here's a typical workflow for fatigue analysis:
Installation
# Clone the repository
git clone https://github.com/vamseeachanta/fatigue.git
cd fatigue
# Install dependencies
pip install -r requirements.txt
# Run tests to verify installation
pytest tests/
Basic Usage Example
from fatigue import SNAnalysis, RainflowCounter
from fatigue.standards import DNV_RP_C203
# Load stress history from FEA results
stress_history = load_stress_time_series("stress_results.csv")
# Perform rainflow counting
counter = RainflowCounter()
cycles = counter.count(stress_history)
# Configure S-N curve per DNV-RP-C203
sn_curve = DNV_RP_C203.get_curve(
joint_type="tubular_t_butt",
environment="seawater_cathodic_protection",
thickness=25.0 # mm
)
# Calculate fatigue damage
analysis = SNAnalysis(sn_curve=sn_curve)
damage = analysis.calculate_damage(cycles)
print(f"Cumulative fatigue damage: {damage:.4f}")
print(f"Predicted design life: {1/damage:.1f} years")
Validation and Testing
Every function includes unit tests with documented validation cases. For example, our S-N curve implementation is validated against:
- Hand calculations from DNV-RP-C203 examples
- Published benchmark problems from industry papers
- Cross-validation with commercial fatigue software
- Sensitivity studies for numerical accuracy
def test_dnv_c203_example_5_1():
"""
Validates against DNV-RP-C203 Example 5.1:
Fatigue assessment of a tubular joint.
Reference result: D = 0.127
"""
sn_curve = DNV_RP_C203.get_curve("tubular_t_butt")
cycles = [(180, 1e5), (120, 5e5), (80, 2e6)]
damage = calculate_miner_damage(cycles, sn_curve)
assert abs(damage - 0.127) < 0.005 # Within 0.5% of reference
Contributing to the Tools
We welcome contributions from the engineering community. Whether you find a bug, want to add a feature, or have a better implementation of an existing function, contributions improve the tools for everyone.
Ways to Contribute
- Bug reports: Found incorrect results? Open an issue with a minimal reproducible example.
- Documentation: Improve docstrings, add examples, or fix typos.
- New features: Propose additions via GitHub issues before implementing.
- Validation cases: Add test cases from published benchmarks or standards examples.
- Code review: Review open pull requests and provide feedback.
Contribution Process
# Fork the repository on GitHub, then:
git clone https://github.com/YOUR_USERNAME/fatigue.git
cd fatigue
git checkout -b feature/your-feature-name
# Make changes, add tests
# ...
# Run tests locally
pytest tests/
# Commit and push
git add .
git commit -m "Add feature: description of changes"
git push origin feature/your-feature-name
# Open a pull request on GitHub
All contributions require tests. For calculation functions, tests must include validation against published references or analytical solutions. We maintain a high bar for accuracy—these tools are used in safety-critical applications.
The Future of Engineering Software
The engineering software landscape is shifting. Several trends favor open-source approaches:
- Python adoption: Python has become the de facto language for scientific computing. Engineers increasingly have the skills to use and contribute to open-source tools.
- Cloud computing: Browser-based tools and cloud execution make it easier to deploy open-source software without local installation hassles.
- Regulatory pressure: Some jurisdictions now require transparency in computational methods for safety-critical applications.
- AI/ML integration: Machine learning models require transparent training pipelines. Open-source tools integrate naturally with modern ML frameworks.
We don't expect open-source to replace commercial FEA solvers—the development investment in those tools is measured in hundreds of engineer-years. But for post-processing, reporting, code checking, and specialized calculations, open-source tools offer compelling advantages.
Conclusion
Open-source engineering tools represent a fundamental shift in how computational methods are developed, validated, and shared. Transparency builds trust. Validation becomes verifiable. Custom requirements become achievable.
For engineering decision-makers evaluating consultants, ask about their computational methods. Do they use proprietary black boxes exclusively, or do they employ transparent methodologies that can be independently verified? The answer reveals something about their commitment to quality and accountability.
For practicing engineers, consider contributing to open-source tools in your domain. The collective benefit of shared, validated computational methods far exceeds the individual investment. When the next engineer validates your implementation against a new benchmark problem, they strengthen the tools that everyone uses.
Explore our repositories on GitHub. Try the tools on your own problems. Open issues when you find problems. Submit pull requests when you have improvements. Together, we can build engineering software that's as transparent as the calculations it performs.