Appearance
Running Simulations
Execute and manage process simulations
Simulation Types
ErgoPlanner supports two simulation modes:
| Mode | Description | Use Case |
|---|---|---|
| Steady-State | Time-independent equilibrium | Design verification, sizing |
| Dynamic | Time-varying response | Upsets, startup, optimization |
Steady-State Simulation
When to Use
- Initial design verification
- Process sizing calculations
- Mass balance analysis
- Effluent quality prediction
- Equipment capacity checks
Running Steady-State
- Prepare: Ensure all units are connected and configured
- Click: Run Simulation button (or press
F5) - Select: Steady-State mode
- Start: Click Start Simulation
Convergence
The simulation iterates until:
- Mass balance errors < tolerance (default 0.01)
- Maximum iterations reached (default 100)
- User stops simulation
Viewing Progress
| Indicator | Meaning |
|---|---|
| Progress bar | Iteration progress |
| Residual plot | Convergence tracking |
| Status | Running, Converged, Failed |
Dynamic Simulation
When to Use
- Diurnal variation response
- Upset condition analysis
- Controller tuning
- Startup/shutdown procedures
- Process optimization
Configuration
| Setting | Description | Typical Value |
|---|---|---|
| Duration | Total simulation time | 1-30 days |
| Time Step | Integration step size | 1-15 minutes |
| Output Interval | Results storage frequency | 1-60 minutes |
| Initial Conditions | Starting state | From steady-state |
Running Dynamic
- Initialize: Run steady-state first (recommended)
- Configure: Set duration, time step, outputs
- Define Events: Add disturbances, setpoint changes
- Start: Click Run Dynamic
Dynamic Events
Define time-based changes:
Event: Flow increase
Time: Day 1, 08:00
Parameter: Influent flow
Change: 150% of average
Event: Load spike
Time: Day 2, 12:00
Duration: 2 hours
Parameter: Influent COD
Value: 800 mg/LSimulation Settings
Solver Options
| Option | Description |
|---|---|
| Method | Runge-Kutta 4 (default), Euler |
| Tolerance | Convergence criterion |
| Max Iterations | Iteration limit |
| Relaxation | Under-relaxation factor |
Biokinetic Settings
| Setting | Options |
|---|---|
| Model | None, ASM1, ASM2d, ASM3 |
| Temperature | 5-35 °C |
| pH | 6.5-8.5 |
| Kinetic Parameters | Default or custom |
Output Options
| Option | Description |
|---|---|
| Parameters | Which variables to record |
| Interval | How often to save |
| Format | Internal, CSV, JSON |
Simulation Controls
Toolbar Controls
| Button | Action | Shortcut |
|---|---|---|
| ▶️ | Start/Resume | F5 |
| ⏸️ | Pause | Shift + F5 |
| ⏹️ | Stop | Ctrl + Shift + F5 |
| ⏭️ | Step | F6 |
| 🔄 | Reset | Ctrl + R |
During Simulation
Real-time actions:
- Adjust setpoints
- Toggle units on/off
- Modify controller parameters
- Add events
Monitoring:
- Watch key parameters
- View trending charts
- Check warnings/errors
Results
Automatic Results
After simulation:
- Stream compositions updated
- Unit performances calculated
- Mass balance computed
- Energy consumption summed
Results Display
| View | Content |
|---|---|
| Canvas | Stream labels with values |
| Properties | Selected item results |
| Results Panel | Tables and summaries |
| Charts | Trend plots (dynamic) |
Accessing Results
- Click stream: Show stream data
- Click unit: Show unit performance
- Results menu: Open results panel
- Export: Save results to file
Troubleshooting Simulations
Convergence Issues
| Symptom | Cause | Solution |
|---|---|---|
| Not converging | Poor initial guess | Run simpler case first |
| Oscillating | Stiff system | Reduce time step |
| Very slow | Large network | Check for loops |
| Negative values | Invalid parameters | Check unit configurations |
Common Errors
"Flow imbalance detected"
- Check all streams are connected
- Verify splitter/mixer ratios
- Look for disconnected units
"Negative concentration"
- Review influent composition
- Check reaction stoichiometry
- Verify kinetic parameters
"Solver failed"
- Reduce time step
- Simplify initial conditions
- Check for numeric overflow
Performance Tips
- Start simple: Get basic case working first
- Build up: Add complexity gradually
- Check intermediate: Verify each section
- Use basic mode: For initial troubleshooting
- Save checkpoints: Before major changes
Advanced Features
Sensitivity Analysis
Test parameter variations:
- Select parameter to vary
- Define range (e.g., ±20%)
- Run multiple simulations
- Compare results
Scenario Comparison
Compare different designs:
- Create base case
- Duplicate and modify
- Run both scenarios
- Generate comparison report
Batch Simulations
Run multiple cases automatically:
- Define parameter matrix
- Configure output settings
- Start batch run
- Review results table
Best Practices
Before Running
- [ ] All units connected
- [ ] Influent defined completely
- [ ] Effluent node present
- [ ] Return streams connected
- [ ] Controllers configured
During Development
- Run frequently to catch issues early
- Use basic mode initially
- Switch to advanced for final design
- Document assumptions
For Reporting
- Run steady-state for design basis
- Run dynamic for sensitivity
- Export results for documentation
- Include convergence info
Next Steps
- Analyzing Results - Interpret simulation output
- Controllers Overview - Add process control
- Dynamic Simulation - Advanced dynamics