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Tutorial 10

Run transient Flowfield playback.

Store physical-time frames and use transient playback for preliminary unsteady design insight.

What you will learn

How to configure transient mode, choose initial condition and time-step behavior, run the solve, and use playback controls.

Prerequisites

A solved engine case and a Flowfield Studio configuration eligible for transient solve. This build supports first-order inviscid transient playback; unsupported combinations are blocked before launch.

Steps

  1. Open Flowfield Studio. In Setup, use 2D inviscid Euler.
  2. Open Solve and set Mode to Transient (time-accurate). The transient settings panel appears.
  3. Choose IC. Cold start / ambient external domain initializes frame 0 to ambient gas at rest. Previous steady/warm start (explicit) uses a previous compatible steady result explicitly and is not an engine startup transient. Chamber/inlet initialized, plume ambient (not available) is shown but disabled.
  4. Choose dt mode: Fixed user dt or CFL-limited dt. For fixed dt, enter dt (s) or click Suggest for an advisory estimate.
  5. Set Target CFL, Stop by, Steps or Final t (s), Save every, and Max frames.
  6. Click Run transient. The solve stores saved frames for playback; playback does not recompute the solve.
  7. Use the Transient playback strip: |<, <, Play, >, >|, the frame slider, Speed, Loop, Ping-pong, and Export.
  8. Read the frame label for frame/time/step/initial-condition context, then inspect Verification and Analysis for residual/convergence status and boundary warnings.
Flowfield Studio transient settings and playback controls
Transient setup and playback controls.

Expected result

The viewer plays saved transient frames with the selected scalar field. Boundary time-of-flight and density-gradient warnings, when present, help decide whether the domain or final time needs adjustment.

Common notes

  • Transient playback is preliminary and first-order inviscid in this build. Use it for design insight and validation planning with the reported boundary and convergence status.
  • Speed controls presentation speed in saved frames per second; it is not physical time scaling.
  • Large frame counts and fine meshes can be refused before launch to avoid excessive memory use.