TIAN Xin-chi,MA Hong-xia,XUE Bo,et al.Effect of Moisture Content on Heat Transfer during Hot-Pressing Process of Bamboo Scrimber with Different Densities[J].Chinese Journal of Wood Science and Technology,2022,36(05):50-55.
TIAN Xin-chi,MA Hong-xia,XUE Bo,et al.Effect of Moisture Content on Heat Transfer during Hot-Pressing Process of Bamboo Scrimber with Different Densities[J].Chinese Journal of Wood Science and Technology,2022,36(05):50-55. DOI: 10.12326/j.2096-9694.2022037.
Effect of Moisture Content on Heat Transfer during Hot-Pressing Process of Bamboo Scrimber with Different Densities
Due to the influence of moisture content during hot pressing, the heat transfer and mechanical properties of bamboo scrimber will be different. During the hot pressing process, there will be a "boiler effect" that the core layer temperature raised sharply, leading to change in the hot pressing cycle of plates. The influence of moisture content on hot pressing heat transfer and "boiler effect" of slabs with different densities was investigated, and the mathematical model of temperature raised time with different moisture content and densities was established. The results showed that due to the influence of "boiler effect", under the same density, the heating time was gradually shortened with the increase of water content; In the pressure maintaining stage, the maximum temperature and temperature raised with the increase of water content. When the density was 0.90 g/cm,3, the cooling time of the plate increased first, and then decreased with the increase of water content. When the density was 1.05 g/cm,3, and 1.20 g/cm,3, the cooling time decreased with the increase of water content. Therefore, in actual production, when pressing plates with a density greater than 1.05 g/cm,3, it was recommended that the moisture content be controlled at about 15%. This study provided a reference for the hot pressing process of bamboo based fiber composites.
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