Two-Dimensional Finite Element Heat Transfer Model of Softwood. Part II. Macrostructural Effects

Authors

  • Hongmei Gu
  • John F. Hunt

Keywords:

Finite element analysis, transient heat transfer, ring orientation, earlywood/latewood ratio, density, thermal conductivity

Abstract

A two-dimensional finite element model was used to study the effects of structural features on transient heat transfer in softwood lumber with various orientations. Transient core temperature was modeled for lumber samples "cut" from various locations within a simulated log. The effects of ring orientation, earlywood to latewood (E/L) ratio, and ring density were related to transient heat transfer. Quartersawn lumber was predicted to have a higher heat transfer rate than that of plainsawn lumber, and lumber containing pith may have a lower heat transfer rate than peripheral lumber. The model predicts that the denser the wood material, the slower the transient core temperature response. The effects of heat transfer and thermal storage (thermal diffusivity) are discussed. The two-dimensional finite element model is useful for studying transient heat flow in softwood lumber cut from any location in a log. The development of the model is described in Part I of this series. Part III addresses the effects of moisture content on thermal conductivity. Part IV addresses the effects of moisture content on and transient heat transfer in lumber.

References

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Published

2007-06-05

Issue

Number 4 / October 2006

Section

Research Contributions

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