Summary: |
Since the performance simulation of buildings, such as fire/smoke spread, energy loss/gain, acoustics, etc. greatly rely on building geometry, the way the physical environment is modeled can substantially effect the reliability of the predictions made by such simulations. Most computer models that simulate fire and smoke spread in buildings limit the computer representation of the building to simpler geometries and define rooms as rectangular spaces or as spaces with uniform crossections. Such a definition does not account for the variety of building elements that can exist in a building such as large overhangs, half height walls, etc. Existing simulations are typically developed as mathematical models and use the principles of thermodynamics to represent the spread of the elements of fire through space over a given time period. For example, in zone models each room is defined as a two tier space with heat and smoke exchange between lower and upper tiers as the fire progresses. On the other hand, field models divide the space into small contiguous units where thermodynamic state of each unit is calculated as the simulated fire progresses. Dynamic processes such as fire and smoke spread must recognize both intangible (i.e. voids) and tangible (i.e. solids such as walls, balconies, ceiling, etc.) architectural entities. This paper explores the potential of solid modeling techniques in generating geometric definitions for both solid and void architectural entities that can interact With mathematical models of fire/smoke spread in buildings. The implications of cellular spatial partitioning techniques for zone or field models of fire/smoke spread are investigated, and the methods of creating cellular decomposftion models for architectural spaces as well as for spatial boundaries such as walls are explored. The size of each cellular partition, i.e. the resolution of the partition, and the material and heat transfer attributes of each cell were found to be very critical in modeling the spread fire through voids as well as through solids in a building. |