Computational Fluid Dynamics (CFD) has the potential to overwhelm any computer, including the largest super computers, with generated flow field data (e.g., pressure, velocity) for transient (time dependent or time accurate) simulations. The traditional approach to transient simulations, and still widely used today, is to run a transient simulation and store entire flow field data sets at each time step for post processing at a later date. Given that a transient simulation can run for 10,000s of time steps, data management clearly becomes a significant issue, or more often a headache. However, there is an elegant alternative - co-processing.

CFD Co-Processing for a Transient Simulation in Caedium

Co-processing extracts results (e.g., pictures, plots) from the flow field data concurrently while the CFD simulation is running, so at any given time there is only a single data set to manage. An added benefit of co-processing is that results can be immediately reviewed and any simulation problems can be immediately addressed. With traditional end of simulation post-processing it is usually a long excruciating wait before problems are found, likely having wasted valuable time and computing resources.

Co-processing can reduce a flow field to a meaningful 3D visualization (e.g., streamlines, contours, vectors) or a simple 2D plot (e.g., pressure distribution, lift monitor) just as with traditional post-processing and then immediately present it. Images can be created, plot data (e.g., surface data) can be exported, image frames can be combined to form movies - just as with traditional post-processing, but concurrently.

CFD Co-Processed Movie Created in Caedium

Co-processing requires that you identify results you want to see before running a transient simulation, whereas traditional post-processing doesn't.

While co-processing shines in dealing with transient CFD simulations, it is also useful for examining and then steering steady-state simulations too. The intermediate results prior to convergence of a steady-state simulation are not physically valid, but they do provide an insight as to whether the simulation settings need to be modified.

Co-processing is a core feature of Caedium to make CFD manageable on resource limited computers. Caedium can create movies (with the option to use high-quality ray tracing for each frame) and export images/data all concurrently while the CFD simulation is running.

For a transient CFD Caedium tutorial that uses co-processing see "Incompressible Transient Flow with Heat Transfer".