DNV Software is pleased to announce that Phast 6.54 has undergone extensive beta testing over the summer and will be released in November.

The major objective for this release is to provide support for Microsoft Vista. This has required updating of third-party GIS and licensing components. In addition, this release is compatible with Microsoft Office 2007.

As well as support for MS Vista and MS Office 2007, the release contains many functional enhancements, some of which were briefly described in DNV Software News No. 1/2008.

A number of improvements have been made to the discharge modelling, giving more control over certain aspects of the calculations. For example, for impinged releases, it is now possible to provide a user-defined velocity modification factor, to manually cap the velocity of the release and to define the angle of the release
from the horizontal.

In addition, for any release users may set the maximum final discharge velocity to a fixed value or use the ‘sonic’ velocity for the material released. They can also override the calculated discharge coefficient with a value of their own for a leak or fixed duration release.

For releases within buildings, much greater control is now possible of the behaviour of the liquid part of the release. Previously, either all the liquid was retained in the building or all was released as vapour. It is now possible to release a proportion of the liquid as vapour from the building. A new dispersion parameter has been added to make it possible to allow droplets trapped in the building to be released as vapour when using the ‘In-Building Release’ model, assuming some liquid evaporation within the building.

We have also made some major improvements to Warehouse Fire Model, which is used to predict emissions from the combustion of pesticides or other warehouse materials by creating a ‘Warehouse Reference Mixture’ based on combustion products. This is then dispersed in the normal way.

The main improvements are:

• The ability to override pesticide molecular weight in case all the atoms cannot be specified in the structural material formula
• The ability to define the warehouse area directly and allow it to be part of a larger building
• The ability to automatically generate scenarios based on the Dutch PGS-15 directive.

All scenarios, whether automatically generated or user-defined, are managed in a single list within the Fire Scenarios tab under each warehouse model.

Improvements have also been made to the risk-ranking reports, where additional information is available showing specific contributions to risk from individual outcomes, weathers and weather directions. Other general enhancements in this release include effect zones available from graphs as well as on maps, a method to select short duration effects for immediate ignition and an option to include solar radiation in thermal radiation results.

A full description of all the improvements in Phast 6.54 can be found in the software release notes.