An experimental study of some line fires
Abstract
Flame length, velocity, temperature and mass flux measurements for some line fires are reported. As would be expected from theoretical considerations, laminar flame lengths are shown to scale as Q1 whilst turbulent flames scale as Q1 The velocity and temperature data in and above the turbulent flame system are shown to be reduced by a scaling related to flame length in a very similar manner to axisymmetric systems. An interesting adjustment occurs just above the flame tip as the constant velocity associated with the ‘intermittent’ flame region decays to a new, apparently different constant velocity associated with the non-reacting plume. The air entrainment coefficient deduced for the non-reacting, buoyant plume region in the Boussinesq approximation and assuming Gaussian distributions for horizontal velocity and temperature is 0.13.
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