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Time Dependency

Understanding steady state and transient flows in CFD

Most Common in CFD

These two time formulations cover 95% of all CFD simulations in engineering applications.

Steady State
Time-averaged solution approach. Fast computation with good engineering accuracy for most industrial applications.
Best for
HVAC analysis, heat exchangers, aerodynamics, and most thermal management applications where time-averaged results are sufficient.
Transient (Unsteady)
Time-accurate solution capturing temporal evolution. Essential for time-dependent phenomena and detailed flow physics.
Best for
Mixing processes, start-up scenarios, oscillating flows, heat-up/cool-down cycles, and any time-critical analysis.

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