Thermal conductivity values for ash, oak, silver wattle, poplar, and beech were measured. Thermal conductivity coefficients of the wood species were determined for radial and tangential directions at four different moisture conditions, ranging from 0 to 22 percent moisture content (MC). Equations predicting thermal conductivities of the wood species according to the MC are proposed in the tangential and radial directions. The thermal conductivity test was performed with a quick thermal conductivity meter based on the ASTM C1113-99 hot-wire method, and measurements were carried out at a room temperature of 20°C to 24°C. The effect of density and porosity on thermal conductivity was also investigated. Results showed the behavior of all wood species studied is quantitatively similar. Thermal conductivity increased with increasing MC. Tangential thermal conductivity values within the MC range of 0 to 22 percent changed from 0.089 to 0.147 W/m-K for poplar, 0.127 to 0.222 W/m-K for beech, 0.113 to 0.202 W/m-K for ash, 0.142 to 0.290 W/m-K for silver wattle, and 0.130 to 0.219 W/m-K for oak. Tangential thermal conductivity was similar to radial thermal conductivity. Radial thermal conductivity was 1.08 times tangential thermal conductivity for poplar, 1.01 times for beech, 1.06 times for ash, 0.95 times for silver wattle, and 1.03 times for oak, respectively. The data are useful when calculating the energy required to kiln-dry lumber and predicting the thermal insulating qualities of log homes made from the species.
The author is a member of the Technical Education Faculty, Karabu¨k Univ., Dept. of Furniture and Decoration Education, Karabük, Turkey (email@example.com). This paper was received for publication in March 2009. Article no. 10589.