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近几年来,应用远红外线干燥木材取得了一些成绩。不仅干燥设备有所更新,干燥工艺有所改进,而且在理论上进行了一些有益的探讨。目前,争论较多的问题是在远红外线加热干燥木材过程中,木材内是否存在“正热源”。有的从“非匹配吸收”理论出发,论证了试样内部温度变化呈抛物线形状,最高温度θ_m在试样中部。还有的提出在3.5～5.5μm波段,表面吸收较少,大部分穿入木材内部。从而得出:在木材内层有一“正热源”存在,即内层温度高于表层。对此问题,我们想谈谈自己的看法。
In recent years, the application of far-infrared drying wood has made some achievements. Not only drying equipment has been updated, the drying process has improved, but also in theory, some useful discussions. At present, the more controversial issue is whether there is a “positive heat source” in the wood during far-infrared heating and drying of the wood. Some from the “non-matching absorption” theory, demonstrated that the temperature changes within the sample was parabolic shape, the maximum temperature θ_m in the middle of the sample. Some also proposed in the 3.5 ~ 5.5μm band, the surface less absorbed, most of the penetration into the wood interior. It follows that there is a “positive heat source” in the inner layer of wood, that is, the inner layer temperature is higher than the surface layer. We would like to talk about our own views on this issue.