Correct modeling problems
Check that the submitted model admits a steady physical solution before changing numerics.
Validate the request and mesh
Submit a dry run and resolve every geometry or boundary-validation error. Inspect the mesh for closed passages, missing components, collapsed gaps, extreme local refinement, and geometry changed unexpectedly by fusing or culling.
Check the flow conditions
For forced flow, confirm that fluid has a complete path between its driving condition and a compatible pressure condition. Check that:
- inlet, outlet, flow-rate, and fan conditions do not demand incompatible flow directions or rates;
- an outlet is not placed inside strong recirculation when its condition assumes outflow;
- passive openings use a condition that supports the expected flow reversal; and
- fan curves cover the simulated operating range rather than remaining clamped at an endpoint.
A closed natural-convection case does not require an inlet or outlet, so apply these checks to the intended model rather than mechanically adding boundaries.
Check the thermal conditions
Every positive heat source needs a path for energy to leave through flow, a fixed-temperature wall, a negative heat load, or another suitable thermal boundary. A powered, closed, fully adiabatic model has no steady energy solution.
Verify power signs and units, thermal boundary signs, material properties, CTM face contacts, and the reference temperature used by buoyancy and temperature safeguards. Large or unintended property jumps can also make the energy system difficult even when the model is valid.
See also
- Boundary placement and defaults explains which surfaces receive default conditions.
- Flow boundary conditions explains the supported flow directions and field treatment.
- Thermal boundary conditions explains heat-input signs and adiabatic defaults.