Internal Pressures for Large-Scale Vented Deflagration Tests

Jet fire is a major hazard in the chemical processing industry.  In many fire accidents one or more obstruction(s) are present between the flames and the target of interest, which may affect the flame shape and position, thus partially blocking the thermal radiation.  As a result, the thermal radiation intensity and resulting level of damage experienced by the target of interest may be significantly affected by the obstruction(s) and would require Computational Fluid Dynamic (CFD) modeling of the fire to accurately capture these effects.  Like any other modeling, CFD modeling requires validation against experimental data before use as a defensible, predictive tool for hazards/risk assessment and fire protection design.

In this study, CFD code was used to model jet fires of three different configurations: (1) horizontal free field jet fire with wind blowing in the same direction, (2) jet fire released 45 degrees upward with cross wind, and (3) impinged on a wall with cross wind.  Full-scale testing was performed to validate the calculations, and in all three cases the predicted flame size and shape are very close to experiment results.  For the impinged case, wall surface temperature as a function of time was calculated and agreed reasonably well with test results.