Experimental tools applied to ignition study of spruce wood under cone calorimeter

A study of wood ignition was performed using a dedicated experimental setup including a cone calorimeter. This setup mainly includes a non-intrusive metrology by infrared camera, enabling an accurate surface temperature measurement and a fast visible camera (3000 fps), used to observe the auto ignition location. The study was carried out in vertical orientation only. Fast visible camera pictures showed three types of ignition: auto-ignition close to the exposed surface, auto-ignition far from the exposed surface and ignition piloted by the cone coil. Ignition occurred only above 45 kW.m(-2). Besides, for low heat fluxes, no ignition occurred but it was possible to observe a transition between pyrolysis solely, without combustion, and smoldering combustion for a sample surface temperature around 400 degrees C.