Smoke and heat exhaust ventilation (SHEV) system design using CFD

  • EN 12101-5, NEN 6093, NFPA 204, NBN S21-208
  • Available Safe Egress Time (ASET)
  • Large smoke compartments
  • Single or multi storey buildings
  • Mezzanine floors
  • Warehouses with palletized or racked storage
  • Shopping malls
  • Atria
  • Complex buildings
  • Mechanical and/or natural
  • Places of entertainment and public assembly
  • Un-compartmented spaces

Smoke and heat exhaust ventilation systems (or SHEVS) are commonly applied in buildings by means of mechanical or natural ventilation systems for extracting smoke and heat in case of a fire. While designing a SHEV system, CFD simulations overcome the limitations of hand calculations described in design standards. A simulation is suitable for any building type and can account for details like wind effects, large smoke compartments and the adverse effect of supply air on a stratified smoke layer.

Interested in a smoke and heat exhaust ventilation systems (SHEV) analysis


By preventing the accumulation of smoke and heat in buildings the available safe egress time (ASET) is prolonged and reaching flash-over conditions is avoided.

Designing well-performing SHEVs requires accounting for numerous parameters such as fire type and size, building geometry, openings, weather effects, etc. The system can be designed following widely applied prescriptive standards (e.g. NEN6093, BRE 368, NBN S21-208-2 and NFPA 204), or good practices. The European standard EN 12101-5 is most commonly used when designing various buildings.

For cases in which the standards offer restrictive solutions or fall short, Computational Fluid Dynamics (CFD) simulations can be used to make the entire design, optimize an existing design, and/or verify the performance of a SHEV system. A CFD is suitable for any building type and can account for details like wind effects, large smoke compartments and the adverse effect of supply air on a stratified smoke layer. The latter can be of significant influence on the smoke layer and thus the operation of the system. Ultimately, a CFD report provides the evidence that the SHEV system is designed well and a building permit can be obtained.

What do we offer

We have an in-depth knowledge of Fire Safety Engineering and a long history in the application of CFD in this field. A significant increase is seen in performance-based building designs being put into practice. Developments in engineering tools and the higher performance of calculation computers allow for going beyond the back-of-the-envelope methods and allow designers to push the boundaries of their building design. One Simulations makes use of industry-leading calculation software and performs calculations on an in-house dedicated high-performance computing (HPC) cluster. This allows us to increase accuracy, with significantly reduced simulation run times and thus shorter turnover times.

Aside from executing the calculations, our team also regularly performs third-party reviews for CFD projects. We can review CFD simulations executed in any software, such as Ansys CFX, Fluent, Fire Dynamics Simulator (FDS), OpenFOAM, etc. See also second opinion services.

While our work cost-effectively gives freedom to designs, the results are reported with a focus on code compliance and legislative requirements.

Feel free to contact us at an early stage so that we can share our knowledge and experience with you.

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