木材干燥预热时间初探

Determination of preheating time during wood drying

预热是木材干燥的重要环节 ,实践中一般仅凭经验来确定预热时间 .该文对木材预热时间进行了理论计算和试验验证 ,并将试验数据与经验预热时间进行了对比分析 ,讨论了木材厚度、预热温度、含水率、基本密度对预热时间的影响程度 .试验及分析结果表明 :①理论预热时间与试验值很接近 ,通过理论计算来确定木材的预热时间是可行的 .②经验预热时间与试验值相差很大 ,其比值介于 2 2～ 8 6之间 .③木材含水率和基本密度对预热时间无显著影响 ;预热温度对预热时间有一定的影响 ;木材厚度是影响预热时间的最主要因素 .

The theoretical calculation and experimental determination of wood preheating time were conducted, the latter was compared with empirical data, and the factors affecting preheating time were discussed. The results indicate that: (1) There is no significant difference between theoretical and experimental preheating time, which indicates that it is feasible to confirm preheating time by theoretical calculation. (2) The empirical time is much longer than experimental data, and the ratio varies from 2.2 to 8.6. (3) Wood moisture content and basic density have no significant effect on preheating time. To some extent, preheating temperature has effect on preheating time. Wood thickness is the main factor affecting preheating time of wood.