基于微波真空干燥的圆竹材干缩性研究

圆竹材的合理干燥是决定竹材利用质量优劣和寿命的重要环节,圆竹材的微波真空干燥,是一项探索性研究课题。笔者采用微波真空干燥方法,在一定的干燥基准条件下,依据含水率变化曲线,将干燥过程分为加速,恒速和减速干燥三个阶段。研究结果表明,干燥初期随着温度逐渐上升,水分蒸发量逐渐增加,中期恒速干燥阶段,大量液态水转化为水蒸气排出,持续时间长,后期减速干燥阶段含水率较低,主要是结合水的蒸发,含水率变化很小,三个阶段所占干燥时间分别约为20、90 min和40 min;沿壁厚方向干缩率不明显,沿着竹竿高度方向由下向上,干缩率逐渐增大。Rational drying of round bamboo culms is a critical step determining the utilization quality and service life of bamboo. Microwave vacuum drying of round bamboo culms is an exploratory research topic. In this study, the authors adopted the microwave vacuum drying method, and divided the drying process into three stages—acceleration, constant rate and falling rate drying stages—based on the moisture content change curve under a specific drying schedule. The results showed that at the initial drying stage, the water evaporation volume gradually increased as the temperature rose; in the medium-term constant rate drying stage, a large amount of liquid water was converted into water vapor and discharged, and this stage had a long duration; in the late falling rate drying stage with low moisture content, the evaporation was mainly of bound water, with minimal change in moisture content. The proportions of drying time occupied by the three stages were approximately 20, 90 and 40 minutes, respectively. In addition, the shrinkage rate along the wall thickness direction was not significant, while the shrinkage rate gradually increased from bottom to top along the height direction of the bamboo culm.

搜集汇总

背景与挑战

背景概述

该数据集研究了圆竹材在微波真空干燥条件下的干缩特性，将干燥过程划分为加速、恒速和减速三个阶段，并分析了不同阶段的含水率变化及干缩率分布。结果表明，干燥时间分配和干缩率沿竹竿高度方向呈现递增趋势。