Determination of the Surface Emission Factors in Wood Sorption Experiments

The t r a n s p o r t of moisture i n wood can be ma t h e m a t i c a l l y d e s c r i b e d w i t h a good approximation as a sim p l e d i f f u s i o n p r o c e s s , a t l e a s t when the temperature i s c l e a r l y below the b o i l i n g p o i n t of water. The s u r f a c e emission f a c t o r i s an important f a c t o r t o take i n t o account, when s o r p t i o n experiments a r e a n a l y s e d . I n t h i s paper some p r e v i o u s l y p u b l i s h e d data and r e s u l t s from new d i r e c t measurements of the s u r f a c e e m i s s i o n f a c t o r s a r e d i s c u s s e d and compared w i t h v a l u e s obtained from the boundary l a y e r theory.