Intelligent Light and FieldView

Leading the Way With In Situ Extracts

At Intelligent Light, we continue to lead the charge for the adoption of in situ, a technique that can maximize insight from simulation runs while also avoiding the problems caused by saving, storing and moving massive amounts of data. Our work this year shows that using in situ allows the CFD practitioner to increase resolution by saving data at a higher frequency, while still saving far less data overall. This reduces disk space and time to read the data in the post-processing phase.

At the AIAA SciTech 2016 conference this month, I shared our in situ work with the AIAA community in two ways: I presented a paper to the MVCE technical committee titled, "In Situ Infrastructure Enhancements for Data Extract Generation", and I presented an in-booth talk about how to add in situ processing into a solver.

Many of the engineers I met at this year's SciTech are running codes at scale on high performance computers but find it impractical, often impossible, to save all of the data on such systems. In situ enables operations such as visualization and analysis, which have traditionally been performed as post-processing, to be executed in the solver itself as it runs. Instead of writing large amounts of volume data, in situ enables the creation of smaller data products such as images and FieldView XDB extract files. XDB files, for example, capture surfaces of interest as well as scalar and vector fields from the solver and write that data in a compact form orders of magnitude smaller than the standard results file.

GT Rotor visualization. Iso surfaces of Q, colored by Cp. Bottom left includes a cross plane of the mesh.

The paper I presented to the MVCE technical committee, "In Situ Infrastructure Enhancements for Data Extract Generation", describes enhancements made by Intelligent Light to VisIt/Libsim that improve its support for batch-creation of VisIt plots, which can then be exported as XDB extracts. Working with James Forsythe of the US Navy's NAVAIR, the CREATE-AVTM Kestrel solver was instrumented with the latest VisIt/Libsim enhancements for batch support and parallel data writing. Kestrel was run at scales up to 1024 cores using a workflow that produced XDB files every 5 solver iterations, an output frequency far higher than would be attempted with volume-based outputs. Even with writing extracts so often, the in situ production of extract files consumed less than 3% of the overall solver runtime. The set of extract files for a single time step is also 21 times smaller than the corresponding volume data, saving both disk space and time to read in large files for subsequent visualization. Several instances of FieldView operating concurrently processed the resulting XDB files into a movie showing helicopter rotor vortices. One strength of this workflow is that it is parallel from data extraction to extract I/O, all the way through XDB visualization. In addition, the workflow is flexible because XDB extracts provide both geometry and fields that can be visualized, enabling fast data analysis that skips the burden of large I/O using volume data.

Intelligent Light's recent VisIt/Libsim improvements make the process of instrumenting a simulation for in situ simpler than ever before. During the SciTech exhibition, I held a talk in the Intelligent Light booth about how to add in situ processing into a solver. The presentation was well attended by users and solver developers from the US, Japan and Israel. There was much interest in adding VisIt/Libsim and XDB data extraction to solvers and the workflow continues to prove its value.

0 Comments

FieldView 16 and XDBview 2 Now Available

3D PDF export generated in FieldView and seen in Adobe Acrobat Reader® (left) and on a tablet (right). (DrivAer geometry courtesy of TU München, Mesh and simulation by VINAS with Pointwise and Helyx).

3D PDF export, faster data read, reduced memory usage and many more improvements

Just a little less than a year has passed by since our release of FieldView 15 and I am happy to announce that our new version, FieldView 16, is ready for download. While software users sometimes feel like installing a new version is not going to impact them much, I am confident that every single FieldView user will benefit from this release.

You will find that FieldView 16 is faster to read your data than previous versions and will also use less memory. Data read can easily be made even faster and more memory efficient by selecting the right Data Input option. When you don't need to perform Dataset Sampling or to compute a lot of streamlines, select "Less" Grid Processing for faster data input. In cases when you do need that kind of performance, select "More" right from the Data Input panel and you will use more memory to get better performance during you session.

FieldView 16 is the first CFD post-processor to introduce a built-in 3D PDF export. This standard format is a great way to present and share your results, allowing interactive exploration via rotation, zooming, panning and commenting in Adobe Acrobat Reader and in 3D PDF viewer apps.

Other highlights of this release include:

  • New Vertices and Shaded Vertices display types for better insight and fast performance
  • The ability to sweep surfaces coming from an XDB extract and to synchronize this operation between multiple datasets for easy animations and side-by-side comparison
  • More control over the location of Surface Flows
  • A new Growing display type for pathlines animation
  • 10x faster read times for AcuSolve users, compared to FieldView 15
  • The ability to read single-file transient data as steady-state
  • Support for results from FLOW-3D v11

We're also introducing the second version of XDBview. Our free, sharable viewer for XDB extracts, now includes the same sweep capability as FieldView 16 and can now read your CAD geometries in STL format.

To learn more about these new versions, I encourage you to read our What's New in FieldView 16 document (Japanese version).

FieldView 16 is a major release. You will need to request new passwords from Intelligent Light. FieldView 16 passwords will work for both version 15 and 16, but as of this release FieldView version 14 and earlier are no longer supported. If you need to test FieldView 16 with your data or workflows before upgrading, feel free to request additional temporary passwords and we'll be happy to provide them free of charge.

Please contact our FieldView Support Team  or your account manager for more information.


Reduce Data Three Orders of Magnitude while Retaining Full Fidelity

Work presented at the AHS 70th Annual Forum demonstrates that extracts are invaluable for both data reduction and quantitative analysis.

In their paper, "Turbulence Transport Phenomena in the Wakes of Wind Turbines", Jha et al, show that data reduced by three orders of magnitude still retains full fidelity enabling quantitative analysis not possible before.

See the movie created for this project

Review the paper

PAR CFD 2015 Meeting - Reporting on the push toward extreme scale CFD

The image shows volume rendering of AVF-LESLIE results for a turbulent planar flame front.
Click to view animation

Last month at the PAR CFD 2015 meeting in Montreal, Canada, I presented a paper entitled "The Impact of In Situ Data Processing and Analytics upon Scaling of CFD Solvers and Workflows".

This work is based on research under our Department of Energy Phase II grant (Award Number DE-SC0007548) and also work under a DOE grant, through the Office of Advanced Scientific Computing Research (Award number DE-SC0012449).

The latter grant is an effort led by Wes Bethel at Lawrence Berkeley National Laboratory in collaboration with Argonne National Laboratory, Georgia Tech and Kitware. In this work we used the AVF-LESLIE code from Prof. Suresh Menon's lab at Georgia Tech, instrumenting it with VisIt/Libsim.

The goal is to determine the overhead associated with in situ processing in comparison to conventional file based volumetric post-processing at scale. For this paper, ‘at scale’ means on the order of 60,000 cores.

Next year we plan to be at 120,000 cores. To date, AVF-LESLIE has been instrumented with VisIt/Libsim and is now able to directly output FieldView XDB files using 40,000 cores and we're working on new in situ data analysis pipelines that can only be performed in situ.

I enjoyed the meeting and learned a lot about the challenges as we all work toward exa-scale CFD simulations.

IL Announcement

HPCwire report

ASME Verification and Validation Symposium

I had the pleasure of attending this year's ASME Verification and Validation Symposium last month.  Verification, Validation and Uncertainty Quantification is an ongoing focus area for me, so in addition to the Symposium, I attended the 2 day course taught by Bill Oberkampf and Chris Roy, authors of the book, Verification and Validation for Scientific Computing. The course gave me a deeper understanding of the techniques and issues that we need to address to ensure that our simulations are accurate and reliable.  I look forward to bringing what I've learned to my work leading the Applied Research Group.