Combustion initiation and evolution during the first 400 ms in a gas burner at 10 μm

Employing the IR at 10 mu m we record, process, and visualize the combustion ignition process and propagation in a domestic stovetop gas heater, during the first half of a second after the electrical spark has initiated it. We record the IR imagery at a rate of 770 frames per second. Only 315 frames are employed to record the propagation around the heater rim in about 0.4 s. Due to the rapidity of the combustion evolution, the exposure time of 80 mu s was implemented electronically. To the best of our knowledge, this is the first reporting of the exact processes that take place during the combustion initiation, including precise determination of time and place of this occurrence. Furthermore, we believe that this work presents the first description of the combustion evolution during the initial half a second after the successful ignition. The visualization led the designers to implement a more effective and safe design of the electric spark sequence, fuel influx ducts, and the combustion chamber configuration. (C) 2013 Published by Elsevier B.V.