Search for dissertations about: "white layers"

Showing result 1 - 5 of 43 swedish dissertations containing the words white layers.

  1. 1. Boundary layer streaks as a novel laminar flow control method

    Author : Sohrab Sattarzadeh Shirvan; Jens H. M. Fransson; Edward B. White; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layer stability; laminar to turbulent transition; laminar flow control; drag reduction; Tollmien-Schlichting waves; oblique waves; streaky boundary layers; miniature vortex generators; discrete suction;

    Abstract : A novel laminar flow control based on generation of spanwise mean velocity gradients (SVG) in a flat plate boundary layer is investigated where disturbances of different types are introduced in the wall-bounded shear layer. The experimental investigations are aimed at; (i) generating stable and steady streamwise streaks in the boundary layer which set up spanwise gradients in the mean flow, and (ii) attenuating disturbance energy growth in the streaky boundary layers and hence delaying the onset of turbulence transition. READ MORE

  2. 2. From Facets to Flow: The Electrooxidation of Glycerol on Pd-based catalysts

    Author : Jai White; Ann M. Cornell; Gunnar Henriksson; Carina Lagergren; Elena Baranova; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; glycerol; electrooxidation; palladium; nickel; alkaline; HPLC; RDE; glycerol; elektrooxidation; palladium; nickel; alkalisk; HPLC; RDE; Chemical Engineering; Kemiteknik;

    Abstract : Glycerol, a by-product of biodiesel refineries, has uses in industries such as cosmetics, food, and pharmaceuticals. However, its usage is small compared to the amount of glycerol produced from biodiesel production. READ MORE

  3. 3. Characterization of White Layers induced by Hard Turning of AISI 52100 Steel

    Author : Seyed Hosseini; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; white layer; hard turning; IR-pyrometer; nano-sized grains; martensite; cutting temperature; bainite; cubic boron nitride; residual stress; retained austenite; cutting forces;

    Abstract : Hard turning is a machining process applied to metallic materials with hardness above 45 HRC. The process offers high production flexibility and sustainable manufacturing since it allows performing both rough and finishing machining of complex geometries in one single setup. READ MORE

  4. 4. White Layer Formation during Hard Turning of Through-Hardened Martensitic and Bainitic AISI 52100 Steel

    Author : Seyed Hosseini; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; white layers; residual stresses; phase transformation; dynamic recovery; bainite; dynamic recrystallization; carbide deformation; retained austenite; steel; martensite;

    Abstract : Increased demands for flexible manufacturing lines, shorter cycle times and reduced impact on the environment drives the need for optimization of today’s manufacturing. For machining of hardened steel parts (>45 HRC), grinding has been the obvious choice for many decades. However, hard turning has often been considered as a replacement due to e. READ MORE

  5. 5. Composition of lignin in outer cell-wall layers

    Author : Maria Christiernin; Gunnar Henriksson; Gösta Brunow; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Lignin; thioacidolysis; primary wall; middle lamella; Populus balsamifera; Populus tremula L. x P. tremuloides Michx.; Picea abies; Picea glauca; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Abstract : The composition of lignin in the outer cell-wall layers of spruce and poplar has been studied and the data obtained have been compared with those of the mature reference wood in which the secondary cell wall predominates. Materials with exclusively or predominantly outer cell-wall layers were examined. READ MORE