Sökning: "earlywood"

Visar resultat 6 - 10 av 15 avhandlingar innehållade ordet earlywood.

  1. 6. Creep, deformation and moisture redistribution during air convective wood drying and conditioning : air convective wood drying and conditioning

    Författare :Tom Morén; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Träteknik; Wood Technology;

    Sammanfattning : Air convective wood drying is associated with a considerable risk for damage to the timber, especially checking and warping. This thesis contains an analysis of creep and deformation during wood drying related to stress development and susceptibility of checking. Also heat and mass transfer problems in the wood drying process are considered. LÄS MER

  3. 7. Modeling the effects of knots in Structural Timber

    Författare :Christina Foley; Avdelningen för Konstruktionsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material technology; Byggnadsteknik; Building construction; three-dimensional fiber paradigm; fiber deviation; knots; annual growth layer; material matrix; knot bump; structural timber; load carrying capacity; Materiallära; critical knot; knot distance ratio; local principal material directions; stiffness; materialteknik;

    Sammanfattning : The main purpose of the pursued research is to increase knowledge of the effects of knots in structural timber so that characteristics of weaker timber may be determined and applied to improve current grading techniques. In the process, a three-dimensional fiber paradigm was established, which describes variations of local principle material axes in timber containing knots. LÄS MER

  4. 8. A numerical and experimental study of initial defibration of wood

    Författare :Stefan Holmberg; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite element simulations; fracture; deformation; fibre; defibration; wood; Building construction; Byggnadsteknik;

    Sammanfattning : A major drawback of the defibration or refining process in manufacturing pulp is that of its large energy requirements. If the mechanics of the process were better understood, large amounts of energy could probably be saved. The initial defibration seems to be crucial for both the quality of the pulp and the total consumption of energy. LÄS MER

  5. 9. On the fracture behaviour of softwood : a combined experimental and computational study of the interaction between fracture behaviour and material anatomy

    Författare :Lars Olof Jernkvist; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : The propensity for fracture, i.e. failure through separation of the material, is a factor that must be regarded in the design of wooden structures, but also in wood machining operations and drying. LÄS MER

  7. 10. Transverse anisotropy in softwoods : Modelling and experiments

    Författare :Carl S. Modén; Lars Berglund; Lennart Salmén; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Softwood; Cellular solid; Anisotropy; Deformation mechanisms; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Transverse anisotropy is an important phenomenon of practical and scientific interest. Although the presence of ray tissue explains the high radial modulus in many hardwoods, experimental data in the literature shows that this is not the case for pine. LÄS MER