摘要
重组竹在制备过程中内部温度的变化对于板材的物理力学性能都会带来显著影响,而内部温度的变化与板材的密度、原材料的含水率、热压板的板面温度和热压时间均有密切关系。本研究重点探讨了重组竹板材幅面的变化对于板材内部温度变化的影响规律,并建立在其他条件固定的情况下,幅面大小与板材内部温度场变化的预测模型。结果表明,随着铺装幅面的增大,芯层的恒温时间、升温时间、热压周期均有所增大,同时,“锅炉效应”的影响加剧,芯层的最高温度升高。此外,基于灰色预测方法对大幅面板材热压建立了预测模型,经过误差检验,得到模型的精度等级为I级,预测模型的可信度和有效性较好,能够为人造板质量预测方法提供一定的参考。最后,基于原始数据和预测指标,得到200 cm纵向铺装长度时的温度变化曲线,再一次说明了模型的科学性、有效性和准确性。
During the manufacturing process of bamboo scrimber, the change of internal temperature would have a significant impact on the physical and mechanical properties of panels, and the change of internal temperature is closely related to the density of panels, the moisture content of raw materials, the surface temperature of panels and hot-pressing time. Among them, the difference of pavement length would lead to the great difference of internal temperature field. In this study, the experimental verification method and the theoretical analysis method were adopted to explore the influence of variations of formats of bamboo scrimber pavement length on internal temperature changes of the panels. Besides, relevant factors that were significantly affected by the format of panels in their hot-pressing processes were obtained according to the theory of statistical variance analysis. At the same time, a prediction model showing the relationship between the size of the sheets and changes of temperature fields inside the sheets was established while other conditions were fixed. The results showed that, with the increase of the laying scale, the constant temperature time, the heating time and the hot-pressing cycle of core layers also increased. Furthermore, because of the increase of air flow channels, superheated steam accumulated in the core layer could not be discharged smoothly, which exacerbated the “boiler effect”, increased the highest temperature of the core layer and finally increased internal vapor pressure in the sheets. In addition, based on the small sample data, a prediction model was established using the grey prediction method, and the prediction equation of each index was obtained. The model could be used to predict the hot pressing related data of a larger format. After error tests, it was confirmed that the accuracy Grade I of the model was achieved, and the prediction model had high reliability and effectiveness, which could provide certain reference value for the quality prediction of wood-based panels
作者
田心池
于文吉
马红霞
林秋琴
薛勃
杨春梅
TIAN Xinchi;YU Wenji;MA Hongxia;LIN Qiuqin;XUE Bo;YANG Chunmei(College of Mechanical and Electrical Engineering,Northeast Forestry University,Harbin 150040,China;Research Institute of Wood Industry,Chinese Academy of Forestry,Beijing 100091,China;Institute of Forest Industry,Guangdong Academy of Forestry,Guangzhou 510520,China)
出处
《林业工程学报》
CSCD
北大核心
2023年第1期38-45,共8页
Journal of Forestry Engineering
基金
广东省重大专项研发计划项目(2020B020216001)。
关键词
重组竹
铺装幅面
热压传热
锅炉效应
预测模型
bamboo scrimber
pavement width
heat-conduction
boiler effect
prediction model
