McCaffrey Plume Model
Definition
A three-zone empirical model for fire plume centreline temperature and velocity developed by Brian McCaffrey at NIST, with separate power-law relationships for the continuous flame, intermittent flame, and buoyant plume zones.
- Developer
- Brian McCaffrey, NIST
- Zones modelled
- Continuous flame, intermittent flame, buoyant plume
- Predicts
- Centreline temperature and velocity
- Model type
- Empirical, power-law relationships per zone
Common questions
Why does the model need three separate zones instead of one formula?+
Temperature and velocity decay follow different physical relationships close to the fuel source versus far above it, so a single power law cannot capture the flame region and the cooler rising plume equally well, hence three zone-specific relationships.
How is this model applied in fire scene reconstruction?+
Investigators use it to estimate plume temperature and velocity at a given height above a known or suspected fire source, helping assess damage patterns, detector or sprinkler activation timing, and heat exposure to nearby materials.
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