Influence of Mean Free Path on Gas Flow in Wood


  • J. A. Petty


Softwoods, gas permeability, slip flow, mean free path, tracheids, bordered pits


It is shown theoretically that the existence of more than one structural component in the flow path through wood causes the gradient of a graph of superficial gas permeability against reciprocal mean pressure not to be directly proportional to the mean free path of the gas. This is unlike the behaviour of homogeneous media and agrees with previously published experimental data.


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