Dynamic properties during wood humidification

Measurement of the moisture in solid materials is important almost at all industry areas. Removing of the volatile substances is very important step before packing or selling wood items. Inaccurate moisture measurement may affect product quality, lifespan and its price. Large proportion of production processes depend on measurement or control of moisture in some form. Within SIB64 Metefnet project, time stability and moisture penetration dynamics of timber samples by gravimetric method and electrical moisture meters are investigated. Strong focus was oriented on penetration hygrometers, which are mostly used. Device for wood humidification was constructed. It allows multiple samples moistening at defined humidity levels with wet air flowing through chambers. Device consists of 3 chambers, where samples can be placed. In each chamber can be achieved different level of humidity. Moisture inside of samples is continuously measured with humidity sensors working on resistance principle. Different kind of wooden samples can be inserted in chambers and data are stored onto a computer. One of the motivations for construction of this device was increasing the speed of the wooden samples humidification. Nowadays used method of moistening in desiccator needs significantly more time. Article will describe device design and measurement results.