Wednesday, April 7, 2010

FDS/Smokeview Minor Release 5.5

We have just posted a minor release of FDS and Smokeview, version 5.5. Recall that a minor release of FDS means that there will be some change in functionality related to one or more of the following:
  • More accurate properties of various gases and liquids using the JANAF Thermochemical Tables
  • Restoration of the baroclinic torque term in the momentum equation
  • Improved treatment of droplets and sprays
  • Improved treatment of various boundary conditions

You may not notice some of the changes, but because they might affect slightly some results, we decided to release these as a minor release.

Many of these improvements have come as a result of the increased verification work that we see being done by the users. Sometimes we find that very simple test cases submitted to the Issue Tracker reveal a feature of the model that is not working as well as it could. Often, these submittals have nothing to do with fire. They are fundamental thermodynamics issues. Takes us back to the good old days of engineering classes. Thanks to all of you who put together these cases and spend a considerable amount of time working with us to diagnose the problems.

In addition to new versions of FDS and Smokeview, there are updated versions of all the manuals. You'll find some work in the FDS V&V Guides related to developments we refer to as "FDS6", the next major release. We're trying to gradually work in the necessary structural changes to the code to prevent the kind of abrupt change that occurred when we transitioned from version 4 to 5. Hopefully, 5 to 6 will be smoother. We do not anticipate major changes to the input or output formats -- the major changes will be under the hood.