Fire spread in paper arrays

Measurements have been made of the rate of fire spread in a solid fuel array consisting of horizontal paper strips standing on edge, separated by various amounts of space. It is found that ignition transients show evidence of several burning modes and in some cases the steady burning can also occur in two different ways, at different speeds. The steady spread rate correlates with the height spacing ratio for both low and high values, but not for intermediate values. The available fire-spread theories are shown to be self consistent in the sense that the predicted relationship between various measured quantities is verified. However, the absence of the possibility of prediction of burning-zone properties, prevents the prediction of fire-spread rate from first principles.