Performance analysis of multilayer flame-retardant fabric ensembles for different exposure conditions using numerical modeling

Abstract

The present study considers a multilayer fire protective ensemble consisting of Nomex IIIA fabric with a honeycomb weave structure as an outer layer, aramid batting quilted to Nomex as a moisture barrier, and Teijin Conex as an inner layer, and cotton as face fabric. The performance of the multilayer ensemble (in vertical orientation) is analysed numerically for different exposure conditions, namely flame (convective) exposure, radiant heat exposure, and combined convective-radiant exposures with varying airgap widths. A coupled conduction-radiative heat transfer model is presented and solved numerically using an in-house developed code to evaluate the protective performance of ensembles subjected to a higher heat flux. The model and code are validated with the experimental data obtained using the bench top tests (Vertical Thermal Protective Performance (TPP) Tester) for lower heat flux. From the model results, the highest burn time for the protective ensemble is observed under flame exposure and the lowest under radiant exposure.

Keywords:

• Fire protective ensemble
• TPP rating
• thermophysical properties
• combined convective radiative exposure
• burn injuries

Disclosure statement

No potential conflict of interest was reported by the authors.