Running Simulations

Once your simulation is configured, this page covers how to launch, monitor, and manage simulation runs.

Launching a Simulation

1. Review your configuration in the Simulation tab:

   • Solver family selected

   • Turbulence model selected

   • Boundary conditions assigned to all surfaces

   • Solver settings configured

2. Click Run Simulation

3. A confirmation dialog shows:

   • Estimated credit cost

   • Mesh cell count

   • Selected turbulence model

4. Click Confirm to submit the job

The simulation is queued and dispatched for cloud execution.

Job Status

Your simulation progresses through these stages:

Status	Description
Pending	Job submitted, waiting for resources
Queued	Resources allocated, initializing
Running	Solver actively iterating
Completed	Converged or reached max iterations
Failed	Error occurred — check logs

The current status is displayed in the workspace header with color coding.

Monitoring Convergence

Residual Plot

While the simulation runs, the convergence plot updates in real time. The residuals shown depend on the selected physics and solver family. Common residuals include mass, momentum, energy, and turbulence quantities.

All residuals are plotted on a logarithmic scale vs. iteration number.

What to look for:

• Residuals should decrease monotonically (trending downward)

• A converged solution shows residuals reaching a plateau at a low level

• Oscillating residuals indicate the solution is struggling. Consider using more conservative solver settings or reviewing mesh quality and boundary conditions.

Convergence Indicators

Residual Level	Meaning
> 1e-2	Not converged — solution is changing significantly
1e-2 to 1e-4	Partially converged — trends are established
< 1e-5	Well converged for many engineering workflows
< 1e-4	Often acceptable when monitor quantities are stable
< 1e-6	Tightly converged — research-grade accuracy

Tip

For engineering applications, residual targets should be checked alongside monitor quantities. Force, moment, pressure-drop, and heat-transfer values should plateau before you treat the run as final.

Logs

The Logs panel shows real-time solver output:

• Iteration count and residual values

• Solver diagnostics and stability indicators

• Error messages if something goes wrong

• Execution timing

Use the filter and search functions to find specific information in the log.

Simulation Completion

When the simulation completes (converged or max iterations reached), you’ll see:

• Final residual values — How far the solution converged

• Total iterations — How many iterations were run

• Runtime — Total wall-clock time

• Credits used — Actual credit consumption

The results are automatically saved and available in the Results tab.

Failed Simulations

If a simulation fails, check:

1. Logs — Error messages indicate the cause

2. Mesh quality — Poor mesh quality is the most common cause of failure

3. Boundary conditions — Inconsistent or missing BCs cause solver errors

4. Solver settings — Overly aggressive relaxation can cause divergence

Common Failure Causes

Error	Cause	Fix
Floating point exception	Solution diverged	Use more conservative settings and review mesh quality
Negative cell volume	Mesh error	Regenerate mesh, check geometry
Matrix singularity	Isolated cells or patches	Check mesh connectivity
Credit limit reached	Insufficient credits	Upgrade tier or wait for monthly reset

Re-Running

You can re-run a simulation with modified settings:

1. Adjust parameters in the Simulation tab

2. Click Run Simulation again

3. Previous results remain accessible for comparison