VSE knjižnice (vzajemna bibliografsko-kataložna baza podatkov COBIB.SI)
  • Impact of various conventional drying conditions on drying rate and on moisture content gradient during early stage of beechwood drying [Elektronski vir]
    Straže, Aleš ; Pervan, Stjepan, 1967- ; Gorišek, Željko
    An appropriate moisture transport and a control of moisture distribution are needed from the early beginning of drying process, especially at drying of high dense and less permeable hardwoods. For ... determination of suitable process conditions at drying of European beechwood (Fagus sylvatica L.) the unidirectional drying kinetics, with an emphasis of free water removal was researched. We used radially oriented sapwood specimens, having thickness from6 mm to 24 mm (f L = 6 mm). Series of conventional drying processes were carried out in the laboratory tunnel drier at constant climate (T = 30 <C) RH= 85%) and with varying air velocity (v) from 0.6 m/s to 7.6 m/s. During the drying, moisture content (MC), MC gradient and moisture flow were gravimetrically determined at successive time intervals. Drying rate generallyincreased with rising of air velocity and decreased with increasing thickness of wood. Relatively constant drying rate was present at the initial stage of drying of thin specimens (. 12 mm) in a short time interval, when lowair velocity was used (. 2.5 m/s). Increasing of the air velocity (> 2.5 m/s) lead to early irreversible reduction of initial moisture flow and transition to the period of significantly falling drying rate, where the internal mass resistance predominated and caused high initial moisture content gradient. The diffusion barrier was induced at too fast free water removal which controlled further drying rate and significantly prolonged the drying process in continuation.
    Vrsta gradiva - prispevek na konferenci
    Leto - 2010
    Jezik - angleški
    COBISS.SI-ID - 1820553