The energy industry is expanding into new frontiers, often in extreme environments or scale of operations (arctic areas, LNG, deepwater). Standard analysis methods do not demonstrate the effects of these changes with sufficient resolution and there is a need for accurate simulation able to represent higher complexity and greater detail. This is achieved for fluid flow, fire and explosion analysis by applying Computational Fluid Dynamics integrated with advanced risk models. Dynamic structural response issues are addressed with Finite Element Methods.

Purpose

Advanced simulation & modeling addresses difficult consequence simulation issues which are not adequately treated with simpler models. Tools includes computational fluid dynamics and finite element structural dynamics.

Benefits

Cutting-edge analysis tools are used and developed for high risk installations. Business values obtained from the most important services include:

• Explosion design accidental loads on firewalls. Accurate predictions of explosion overpressure and explosion risks are provided. The need for excessive strength of firewalls may be omitted, and the effects of mitigating measures such as segmentation and blowdown, deluge, etc., are quantified, providing the right conclusions to make critical decisions.
• Fire protection in process areas. Transient critical fire loads and fire risks will be calculated and combined with structural response analyses. We weigh risks associated with different protection systems (flare, PFP) giving decision makers the lowest risk solution in co-operation with the design team.
• Integrated fire and explosion analysis, providing optimal solutions for protection from both fires and explosions. These accidents often have contradictory mitigating measures (a firewall, for example, provides fire protection, but causes increased pressures). By weighing the different risks from using the same tool, we can help you make the right decisions about the configuration of decks and walls. Analyses of this kind are recommended in early design or re-buildings, when arrangement decisions are made.
• Integrated windchill and ventilation analysis to find optimal wind protection arrangements that give acceptable comfort for workers and the lowest possible fire and explosion risk. This is also performed with the same risk tools, providing the same degree of accuracy.
• A high degree of accuracy for installations with high risk avoids excessive conservatism of simplified models. CFD tools are the most accurate tools for predicting fires and explosions and, integrated with DNV’s risk analysis tools, they uncover risks in an objective way, also complying with regulative acceptance criteria and ALARP principles.
• Risk communication through graphics/visualisation. Complex 3D fire and explosion phenomena are shown in order to communicate and explain the need for the recommended solutions. For example, a new bridge can be located where fire and explosion loads are the lowest. Fire impact is best shown using 3D plots of the flames.
  

Our approach

We support our customers with the following analysis, either as stand-alone services or in an integrated service package:

• Explosion loads on fire walls and control rooms (Design Accident Load, DAL Overpressure). Deterministic maximum pressures and explosion risk assessment using FLACS and EXPRESS.
• Fire DAL for an area (using KFX); Optimal shutdown and blowdown philosophies, and technical safety.
• Structural response analysis (using FAHTS/USFOS, GENIE and PFPro) for Passive Fire Protection (PFP) optimisation on structure and pipes.
• Integrated probabilistic fire and explosion analysis; optimal protection against both fires and explosions.
• Gas leak dispersion; optimal gas detector location.
• Event gas dispersion; safe air intake locations.
• Fire radiation and smoke dispersion; escape away impairment.
• Exhaust gas dispersion; problem-free exhaust pipe height/location.
• Helideck turbulence analysis; Helicopter operation procedures.
• LNG dispersion and dispersion from gas pipelines in terrain and complex geometries; safe distances.
• Windchill analysis, optimisation of wind walls, and workers’ comfort and safety.
• Flare radiation, cold vent dispersion and optimal stack heights.
• A QRA setting that gives optimal total safety.
• Finite Element Methods address dynamic response of structures, such as for collision analysis for LNG carriers, showing the degree of damage and potential inner tank hole sizes for a range of feasible events. This is used in a risk analysis to develop operational strategies avoiding any release of LNG cargo.