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Journal of Wood Science

Official Journal of the Japan Wood Research Society

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Effect of EMC and air in wood on the new in-process moisture content monitoring concept under radiofrequency/vacuum (RF/V) drying

Journal of Wood Science volume 56, pages 95–99 (2010)Cite this article

Abstract

To improve the accuracy of the new in-process moisture content (MC) monitoring concept under radiofrequency/vacuum (RF/V) drying, equilibrium moisture content (EMC) tests were carried out under various ambient pressures, and pressure curves in wood were analyzed during chamber evacuation and heating phases. The results showed that EMC increased with a decrease in ambient pressure regardless of temperature, relative humidity (RH), and species. The accuracy of MC estimation for Hinoki under RF/V drying was improved from 1.5% maximum absolute errors to 0.6% after EMC modification. The pressure curves for Hinoki and Sugi under RF/V drying showed similar tendencies to an idealized process. Russian larch showed different curves, indicating that the pressure in the wood did not reach the ambient pressure because of its low permeability. Therefore, MC could not be estimated using this monitoring concept because of the presence of much air in the wood of Russian larch.

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Authors and Affiliations

  1. Department of Forest Resources, Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, 790-8566, Japan

    Honghai Liu, Lin Yang, Masatoshi Sugimori & Kazuo Hayashi

  2. Laboratory of Bio-based Material Science and Technology, Northeast Forestry University, Ministry of Education, Harbin, 150040, People’s Republic of China

    Yingchun Cai

Authors
  1. Honghai Liu
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  2. Lin Yang
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  3. Yingchun Cai
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  4. Masatoshi Sugimori
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  5. Kazuo Hayashi
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Corresponding author

Correspondence to Kazuo Hayashi.

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Liu, H., Yang, L., Cai, Y. et al. Effect of EMC and air in wood on the new in-process moisture content monitoring concept under radiofrequency/vacuum (RF/V) drying. J Wood Sci 56, 95–99 (2010). https://doi.org/10.1007/s10086-009-1079-4

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  • DOI: https://doi.org/10.1007/s10086-009-1079-4

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