Investigation of the Vertical Bunsen Burner Test for Flammability of Plastics.

摘要

A vertical Bunsen burner test for flammability of plastics (UL-94V) was studied in an attempt to relate the upward burning of plastics to their material fire properties. It was shown that the heat release parameter, the critical heat flux for piloted ignition, and the thermal response parameter account for most of the fire behavior of plastics in the test. The premixed flame of the Bunsen burner during transient ignition and the laminar diffusion flame of the burning material have nominal heat fluxes of about 60 kW/m2. The heat release rate (HRR) per unit area during burning was a significant factor in correlating UL-94V ratings. The height of the flame, which transfers heat to the burning sample, was proportional to HRR, and critical values of HRR for ignition, sustained burning, and upward flame spread in the test were theoretically estimated to be 80, 250, and 300 kW/m2, respectively.