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Preučevali smo vpliv letnih klimatskih nihanj na postopek sušenja na prostem in možnosti povečanja sušilnih kapacitet ter prihranka energije v tehničnih postopkih sušenja ob smotrni uporabi naravnega sušenja. Postopek sušenja smo izvajali na bukovih vzorcih debeline do 38 mm in ga spremljali od začetka decembra do začetka avgusta v 8 zaporednih serijah. Vzorce smo sušili od svežega stanja do doseženega ravnovesja z okolico. Med sušenjem na prostem smo natančneje preučevali vpliv temperature in relativne zračne vlatnosti na sušilno krivuljo in hitrost sušenja v posameznih letnih časih. Ugotovili smo, da na hitrost sušenja na prostem najbolj vplivajo temperaturna nihanja. Najvišje hitrosti sušenja so bile dosežene v maju in juniju, najnižje pa v decembru in januarju. Hitrost sušenja na prostem se močno zmanjša ob nenadnih padcih temperature, ki povzročijo hitro povečanje relativne zračne vlažnosti. Med kontrolo kakovosti smo ugotovili, da so bili vzorci kakovostno posušeni in brez napak. The research studies the influence of seasonal climatic changes on the process of wood seasoning, explores the possibilities of increasing kiln drying capacity, and saving energy in technical processes of wood seasoning at a reasonable use of air drying. The process of wood seasoning was studied on 38 mm thick beech samples and monitored on 8 subsequent series from the beginning of December to the beginning of August. They were submitted to air drying in fresh state and seasoned until they reached balance with the environment. During air drying of wood the effects of temperature and relative humidity on drying curve and speed in different seasons were studied. The results show that the drying rate is most affected by changes of temperature. The highest drying rates were reached in May and June, the lowest in December and January. The drying rate decreased substantially in the event of a sudden drop of temperature, causing a sudden increase of relative humidity. Through a quality assurance process it was confirmed that the samples were seasoned well and without defects.

Značilna zgradba bukovine ima velik vpliv tudi na njene sušilne karakteristike, ki pogosto izstopajo kot neugodne napake. Z vidika hitrosti sušenja in doseganja ustrezne kakovosti smo primerjali štiri tehnike sušenja: na prostem, komorsko, vakuumsko in visokofrekvenčno. Bukove elemente debeline 32 mm smo sušili iz svežega stanja (uz = 78 %) do ciljne vlažnosti 10 %. Pred sušenjem, med njim in po njem smo določali hitrost sušenja in ocenjevali kakovost z določanjem vlažnostnega gradienta, zaskorjenja in vidnih napak. Najhitrejše je bilo visokofrekvenčno sušenje, vendar omejeno le na sušenje pod točko nasičenja celičnih sten, nekoliko počasnejše je bilo vakuumsko in nato komorsko sušenje. Najdaljše je bilo sušenje na prostem, vendar s še vedno sprejemljivo hitrostjo v začetnih fazah sušenja. Najvišja kakovost sušenja z vidika vlažnostnega gradienta, zaskorjenja in vidnih napak je bila dosežena z vakuumskim postopkom, ki pa tudi ni bilo najugodnejše pri sušenju svežega lesa, kar kaže, da bi optimalne rezultate dosegli s kombinacijo več različnih postopkov. Specific structure of European beech wood (Fagus sylvatica L.) has great influence on its drying characteristics, which are often negatively expressed as various drying defects. Four drying techniques, i.e. controlled air drying,normal temperature kiln drying, vacuum drying and drying with high frequency (HF) were compared to achieve the best technique. Tangential oriented 32 mm thick, 80 mm wide and 800 mm long beech wood samples were dried from green condition (uz = 78 %) to the final moisture content of 10 %. During drying processes wood quality was evaluated regarding to drying rate, time of drying, moisture content (MC) gradient, casehardening and occurrence of drying defects. Drying with the HF was the fastest, followed by vacuum drying and kiln drying. In air drying wood kept good quality, with the lowest MC gradient, however too high MC of wood was achieved. Good final drying quality, concerning casehardening and visual appearance, was achieved at vacuum drying process. Probably the combination of different drying techniquesw ill give the best results.