Open Access3D Modeling and Visualization of Non-Stationary Temperature Distribution during Heating of Frozen Wood
Author(s) -
Nencho Deliiski
Publication year - 2013
Publication title -
drvna industrija
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.287
H-Index - 19
eISSN - 1847-1153
pISSN - 0012-6772
DOI - 10.5552/drind.2013.1306
Subject(s) - defrosting , thermal conduction , mechanics , materials science , thermal , volume (thermodynamics) , contour line , saturation (graph theory) , composite material , geometry , thermodynamics , mathematics , heat exchanger , meteorology , physics , combinatorics
A 3-dimensional mathematical model has been developed, solved, and verified for the transient non-linear heat conduction in frozen and non-frozen wood with prismatic shape at arbitrary initial and boundary conditions encountered in practice. The model takes into account for the first time the fiber saturation point of each wood species, ufsp, and the impact of the temperature on ufsp of frozen and non-frozen wood, which are then used to compute the current values of the thermal and physical characteristics in each separate volume point of the material subjected to defrosting. This paper presents solutions of the model with the explicit form of the finite-difference method. Results of simulation investigation of the impact of frozen bound water, as well as of bound and free water, on 3D temperature distribution in the volume of beech and oak prisms with dimensions 0.4 x 0.4 x 0.8 m during their defrosting at the temperature of the processing medium of 80 oC are presented, analyzed and visualized through color contour plots.Kreiran je i riješen 3D matematički model te provjeren za nelinearno provođenje topline u smrznutome i nesmrznutom drvu prizmatičnog oblika pri proizvoljnim početnim i rubnim uvjetima koji se susreću u praksi. Prvi put model uzima u obzir točku zasićenosti vlakanaca za svaku vrstu drva (ufsp) i utjecaj temperature na ufsp smrznutoga i nesmrznutog drva, koji se primjenjuju pri izračunavanju trenutačne vrijednosti termo-fizikalnih svojstava u svakoj posebno definiranoj točki volumena materijala koji se odmrzava. Rad prikazuje rješenja modela s eksplicitnim oblikom metode konačnih razlika. Rezultati simulacijskih istraživanja o utjecaju zamrznute vezane vode te vezane i slobodne vode na 3D raspodjelu temperature u volumenu bukovih i hrastovih prizmi dimenzija 0,4 x 0,4 x 0,8 m tijekom odmrzavanja pri temperaturi procesnog medija od 80 оC prezentirani su i analizirani te vizualizirani crtežima u boji