The 2009 release of Phast 6.6 will include a significant extension, providing major improvements to the assessment of risks from gas explosions.

DNV Software continuously monitors evolving market needs to ensure that our software products are able to provide the functionality customers need and expect. In recent years, accidents along with new industry standards have driven demand for improved modelling and reporting of the effects of flammable releases. Of particular interest are the effects on people and the likelihood that certain effect levels will be exceeded.

Phast 6.6 will provide more transparency within the risk results and significant improvements in the accuracy with which explosion risks can be assessed in areas of congestion and around occupied buildings. It will also allow more detailed definition of model geometry, specifically in terms of defining degrees and areas of
congestion and location and strength of individual buildings, and the risks within and around those buildings.

The Phast 6.6 release will comprise two main deliverables, which will together provide an ‘integrated’ tool with the extended modelling and reporting of explosion risks available as a chargeable extension:

• An update to Phast based on the existing architecture including the improved mapping of buildings and equipment and extended implementations of the Multi-Energy and Baker-Strehlow-Tang explosion models
• An additional graphing and reporting module based on the next-generation architecture, the so-called Risk Framework, providing significantly enhanced capabilities for analysing and reporting the consequence of and risk from explosions.

Data flow architecture for the Phast explosion risk modelling extension.

Phast 6.6 model in current architectures

• New improved and extended implementation of Multi-Energy (ME) and Baker-Strehlow-Tang (BST) explosion models
• Mapping of areas of congestion, to determine appropriate explosion sources of greatest consequence, and buildings and structures, to assess occupant vulnerability and explosion strength at building locations
• Risk integration calculations.

The extended ME implementation utilises idealised explosion scenario results and rules to define obstructed regions based on the Dutch Yellow Book, correlations to determine explosion strength based on GAME, guidance to resolve obstructed region separation based on RIGOS, and guidance on the combination of multiple explosion sources and comparison with CFD predictions for a number of realworld configurations, both based on GAMES.

Phast 6.6 module in Risk Framework
The Phast Risk application will provide much more detailed information on all major risk contributors. It will contain major improvements to the graphing, reporting and mapping capabilities, particularly for risk assessment and mitigation including:

• Capabilities for analysing and reporting the consequence of and risk from explosions
• New F/N curve graphing with ability to drill down through F/N curves to identify risk contributors from all flammable and toxic outcomes in all fatality ranges
• New graphs of exceedance probability for all effects at specified locations and on individual buildings
• Extended contouring capabilities including the ability to generate exceedance contours for all effect types.
  

From the modelling perspective, an up-dated, more modular and robust Unified Dispersion Model will be included along with improved, more consistent standalone and linked pool vapourisation modelling, and the ability to calculate more concentrations of interest.

Improvements to the GIS functionality provide the ability to import geometry and associated data from external sources (e.g. population density data) which will give much better integration with third party geographical databases.

Please contact us for more information and status of these developments on software.support@dnv.com