Effect of Moisture Content on Thermal Physical Properties and Heat Transfer of Plywood during Hot-Pressing

Abstract:

In order to investigate the effect of moisture content on thermal physical properties and heat transfer of plywood during hot pressing, the quasi steady method was applied to measure the thermal conductivity, specific heat and thermal diffusivity values of the resinated plywood assembly with a UF loading rate of 300g/m2 under different moisture conditions. Results showed that with the increase of moisture content in a range of 10-22%, the thermal conductivity and specific heat of the plywood assembly enhanced significantly, and that plywood hot pressing noticeably consisted of fast heating and slow heating phases: during the first phase the heating rate of the core ply was quickened with the increase of moisture content while the second phase did not show any significant impact of moisture content on the corresponding heating rate.

• Periodical: Advanced Materials Research (Volumes 652-654)
• Pages: 1283-1289
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.652-654.1283
• Online since: January 2013
• Authors: Xiang Liu, Sun Guo Wang, Wen Ding Li, Lei Chen
• Keywords: Heat Transfer, Hot Pressing, Moisture Content, Plywood, Thermal Physical Property

References

[1] Z. Liu and J. Wang: Factors Affecting the Heat Transfer of Particleboard. Journal of Beijing Forestry University. 1995(2): 64-72 (in Chinese)

[2] L. Xie, Y. Yu and J. Cao: Study on Heat Conduction of Dry-process Binderless Fiberboard with Conventional Hot-pressing Methods. China Forest Products Industry. 2003, 30(1): 26-28 (in Chinese)

[3] A. Li: Determination of MDF Thermal Conductivity. China Forest Products Industry. 1997, 24(2):27-30 (in Chinese)

[4] Q. Yang: Theoretical Expressions of Thermal Conductivity of Wood. Journal of Forestry Research. 2001, 12 (1): 43

[5] P. R. Steiner and C. Dai: Spatial Structure of Wood Composites in Relation to Processing and Performance Characteristics. Wood Science and Technology. 1993, 28:45-51

DOI: 10.1007/bf00193875

[6] Y. Lei: Influence of Mat Moisture Content on Heat Conduction during Hot-pressing. China Wood Industry. 2006, 20(6): 20-22 (in Chinese)

[7] C. Xu and Y. Hua: Temperature Behavior within the Mat during SIVP. China Forest Products Industry. 2002, 29(6): 13-15 (in Chinese)

[8] B.G Zombori, F.A Kamke and L.T. Watson: Simulation of the Internal Conditions during the Hot Pressing Process. Wood and Fiber Science. 2003, 35(1): 2-23

[9] J. Wu, Z.Yu and T. Chen: Heat Transfer Process during Hot-Pressing of Flakeboard. Journal of Beijing Forestry University. 2005, 27(2): 92-95 (in Chinese)

[10] Z. Cai, J.H. Mueh and J.E. Winandy: Effects of Panel Density and Mat Moisture Content on Processing Medium Density Fiberboard. Forest Products Journal. 2006, 56 (10): 20- 26

[11] X. Zhang and Z. Ren: Science of Thermal Conductivity (the Forth Edition). Press of Chinese Construction Industry, Beijing, China, 2001: 12-13 (in Chinese)

[12] X. Xu, D. Xu and X. Liu: Investigation of the Heat Conduction Coefficient of Woody Composite Mat Adhered with Liquid UF Resin at Room Temperature. Journal of Nanjing Forestry University. 2012, 36(1):119-123 (in Chinese)

[13] Q. Yang: Theoretical Study of Wood Thermal Characteristics – Thermal Conductivity and Diffusivity of Wood. Journal of Fujian Forestry College. 1992, 12(2): 182-188 (in Chinese)