Concentration fluctuation and ignition characteristics during atmospheric diffusion of hydrogen spouted from high pressure storage

Furthermore, the spectrum of concentration fluctuation was analyzed to decay with −5/3 power of wave number except in the vicinity of nozzle outlet, and the typical characteristic spatial scales of the concentration fluctuation at the beginning of the inertial-convective subrange were about 100 and 200 mm for d = 0.2 and 0.53 mm, respectively. The probability of ignition by using an electric spark and the behavior of flame propagation were examined, and for C < 10%, the flame was once formed and extinguished after a short travel of approximately 100 or 200 mm, which may correspond to the characteristic spatial scale of eddy or inhomogeneous hydrogen distribution.