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 phased development of multi-component modelling continues with this new version of Phast. Following implementation of the new property system in the previous version, work has continued to introduce the capability of modelling multi-component discharge and dispersion. This will be restricted to cases that do not rain-out in this release, but development of this significant piece of work continues; updates on future developments will follow later this year. The first phase includes:
Discharge calculations for leaks, line ruptures, relief valves, disk ruptures, catastrophic ruptures and vent from vapour space
Dispersion of vapour, two-phase and liquid releases which do not rain-out. For two-phase and liquid releases, the new discharge modelling will predict component separation between liquid and vapour phases
New reports of phase compositions after discharge and during dispersion.
Does not currently model rain-out, so no pool modelling
The time varying discharge, long pipeline, in-building and tank roof collapse scenarios, and the user-defined
model are not yet supported.
Automated averaging time adjustment
We have added an option to select the exposure duration to be used as the averaging time without the need for user intervention. This allows toxic effects that are integrated over time to use the matching averaging time. It also better aligns with current guidelines provided in the regulations used in France. Using this option, the exposure time may simply match the release duration for non-quasi-instantaneous single-segment continuous releases. Alternatively, for instantaneous, multi-segment and quasiinstantaneous releases, the exposure times can vary with downwind distance and elevation. There are new parameters controlling the start and end of the exposure period, and new graphs and reports for exposure time. The adjusted concentrations are used to calculate toxic effects; these are used in any subsequent risk calculations. In addition to these two major enhancements in Phast, there are many others which are described in detail in the release notes.
Some of the more useful enhancements are:
Improvements to fire modelling with the ability for users to define their own Surface Emissive Power for jet fires, use the ‘DNV Recommended’ models which will automatically select the most appropriate jet fire model for a given situation and define their own material properties and emissivity for pool fires
Updates to the pool fire materials data to provide improved compatibility with latest literature
Improvements to the route model with the ability to define routes using polylines, have multiple routes in a single study folder, and improved smart-run
Addition of relative coordinates as an alternative way to define the location of objects in the risk version
Improvements to spreadsheet features, with the ability to export to as well as import from spreadsheets and create multiple folder levels in spreadsheets
New version of reports component with more flexible reports, including export to third-party applications and file formats, and much better copy-and-paste capabilities
A number of graphing improvements, including radiation against distance plots for linked flammable models in the risk versions, better facilities for setting graph defaults such as line thickness and style, ability to display areaunder cloud and maximum footprinton legend, rotation of maps, and more intelligent weather selection.
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.
Product:DNV Phast 6.6