Two-Dimensional Heat Flow Analysis Applied to Heat Sterilization of Ponderosa Pine and Douglas-Fir Square Timbers


  • William T. Simpson


Invasive species, heat sterilization, lumber, timber


Equations for a two-dimensional finite difference heat flow analysis were developed and applied to ponderosa pine and Douglas-fir square timbers to calculate the time required to heat the center of the squares to target temperature. The squares were solid piled, which made their surfaces inaccessible to the heating air, and thus surface temperatures failed to attain the temperature of the heating air. The surface temperatures were monitored during heating and related to time by an empirical equation. When this equation was used as the boundary condition in the finite difference solution, calculated time estimates required to heat the center to target temperature agreed favorably with experimentally observed heating times.


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Research Contributions