Abstract:

This paper developed the theory on the three-dimensional flow-resistor network for gas permeability of softwoods from longitudinal to radial and tangential directions. The two-dimensional equivalent connection of the secondary flow-resistor network was presented for the flow of gas in the radial and tangential direction. The method had been given in this paper to determine the number of flow resistor elements in the network and the way to resolve the network. The radial and tangential gas permeability of Masson pine (Pinus massoniana) was evaluated with the flow-resistor network. Comparison is carried out between the calculated and measured values of radial and tangential gas permeability, and result shows that there is agreement between the both. The three dimensional flow-resistor network can be use to describe the mechanism that gas flows through the softwoods and to evaluate the gas permeability in longitudinal, radial and tangential directions provided that the previous work on the longitudinal gas permeability joins up with those done in this paper. The work done in this paper is useful for wood processing.

Key words: Radial gas permeability of wood, Tangential gas permeability of wood, Flow-resistor, Percolation network, Real space renormalization