CGNS Steering Committee

Telecon Minutes

The meeting was called to order with 10 people in attendance. The attendees are listed below.

The minutes of the June Meeting in St. Louis were approved as posted on the web.

• Charter Business - Bob Bush extended an invitation for nominations and volunteers for people to serve as chairman of the Steering Committee beginning next year. The duties include arranging meetings and telecons, setting agendas, serving as a focal point for questions about the standard and organization, coordinating the review, approval and implementation of extensions and generally keeping the lines of communication open. Anyone interested should contact Bob Bush (bushrh@pweh.com) by the end of September.
  
  
• ISO Status - Ray Cosner indicated that there have been no meetings of the ISO committee since the June meeting. Parts 52 an 53 are complete and ready for release. They are available for review on the CGNS web site. Part 110 has been incorporated into Part 237 and which is still being revised. There is still a plan to have a workshop to review the parts once 237 is in draft form, probably towards the end of the year. Ray will try to provide one month notice to the committee of the arrangements.
  
  
• Documentation - Charlie Towne indicated that the Library of Congress number for the AIAA Recommended Practice has arrived and final arrangements are being made to finalize the document. He is now working on revising the beta document to include new extensions currently being implemented.
  
  
• Extensions - Diane Poirier reported on the status of extensions currently being implemented, including Delete Node, Gravity, Axisymmetry, Rotating Coordinates, Periodic Connectivity and Rotor/Stator interactions. These will be released as Version 2.2 as soon as the beta documentation has been updated. There was some discussion about forward compatibility. We will allow forward compatibility for point releases, and reserve changes that are not forward compatible for integer level revisions. This should alleviate much of the vendor support issues. The change has been implemented in V2.1 and will be supported in subsequent revisions. We have also made a Rev release of V2.0 in case vendors would like this capability, but do not want to upgrade to V2.1. Charlie Towne asked if we could pass back an error code instead of stopping the read, but this would be difficult to implement. We will continue to study this issue. Marc Poinot has indicated that he has a full implementation of the SIDS using HDF5 instead of the ADF core, with the notable exception of support for Links. Revisions to HDF5 should facilitate adding Link capability also. Marc has not had time to do performance comparisons between HDF and ADF implementations, and ONERA is still using ADF for their applications. David Edwards indicated a willingness to do some benchmarking and comparisons.
  
  
• Related Software Status - Chris Rumsey will review the utilities and documentation provided by Bruce Wedan, and see what we can provide in the way of documentation.
  
  
• Issues - There was some discussion about bug tracking to provide additional user information about the status of the software. There are free software products out there, but there being no known bugs we will wait to implement a bug tracking system. John Bussoletti would like to see some re-structuring of the mid-level libraries to better support unstructured grids, new programming capabilities and perhaps isolate ADF from the SIDS and mid level library implementation. He also indicated a desire for the addition of unstructured edge definition to the SIDS. The committee invited him to write extensions for the SIDS, and to recommend changes to the mid level library. A bottom up re-write of the mid level library would be welcomed, but the committee does not currently have the resources to support such an activity. Chris Rumsey indicated the continuing need for a diff function to compare binary files. The time stamp difficulty, and the indeterminate node structure were cited as difficulties that would need to be overcome. This also led to a discussion of the need for a SIDS compliance checker, perhaps built into the Utilities.

Attendees