马尾松木材浮压干燥过程中的传质传热特性

该文阐述了在真空状态且浮压条件下马尾松的干燥过程特性,揭示了加热温度、木材含水率、真空度及真空度变化频率对木材表面水分蒸发强度的影响.实验证实,提高温度、真空度和加快真空度变化频率都有利于加快木材内水分的迁移.真空频率加快时,木材内的温度场变化也加快,干燥时间明显缩短.此外,当外界压力不变时,木材表面水分蒸发强度随含水率的提高而增强,纤维饱和点以下更有明显的区别.

Characteristics of heat and mass transfer in drying process of Masson pine lumber under floating pressure

This paper introduces drying characteristics of Masson pine lumber under vacuum and floating pressures, and reveals the effect of temperature, moisture content, vacuity and vacuum changing frequency on water vapor intensity of lumber surface. It is proved that the enhancement of temperature, vacuity and vacuum changing frequency do have advantages to accelerate moisture transfer in wood. When vacuum changing frequency increases, temperature field and moisture field in wood change much faster and then drying period is evidently shortened. At the same time, when vacuity keeps unchanged, water vapor intensity on lumber surface increases with moisture content, especially below FSP.