Sökning: "low velocity impact"

Visar resultat 1 - 5 av 92 avhandlingar innehållade orden low velocity impact.

  1. 1. Damage Tolerance of Impacted Composite Sandwich Structures

    Författare :Moeen ud din Saeed Rajput; Malin Åkermo; Stefan Hallström; Magnus Burman; Christian Berggreen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite sandwich; cellular; polymer; material characterization; modulus; non-crimp fabric; low velocity impact; vibration; uncertainty analysis; drop-weight impact; fractography; barely visible impact damage; X-ray microtomography; compression-after-impact; bending-after-impact; high speed image processing; damage resistance; damage tolerance; Aerospace Engineering; Flyg- och rymdteknik;

    Sammanfattning : This thesis deals with damage tolerance of impacted sandwich structures for load bearing applications. Composite sandwich structures find wide application as lightweight solutions in aerospace components, since weight reduction and less fuel emissions are primary concerns for aircraft manufactures. LÄS MER

  3. 2. Neck injuries in rear impacts : Dummy neck development, dummy evaluation and test condition specifications

    Författare :Astrid Linder; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Neck; Injury; Anthropometric dummy; Severity; Impact test; Rear end collision; Seat; Mathematical model; Velocity; Thesis; Optimization; Mathematical neck models; Rear impact tests; Biomechanics; Road: Components of the vehicle; Road: Components of the vehicle;

    Sammanfattning : The objective of the work underlying this thesis was firstly to develop a neck for a new rear impact dummy, to evaluate the complete dummy and to specify test conditions for a consumer test with attention to AIS 1 neck injuries in rear impacts. In the development of the dummy neck, a mathematical neck model was developed and evaluated. LÄS MER

  4. 3. Terrestrial consequences of hypervelocity impact – shock metamorphism, shock barometry, and newly discovered impact structures

    Författare :Sanna Alwmark; Berggrundsgeologi; []
    Nyckelord :Impact cratering; Impact structure; Shock metamorphism; Shock barometry; Quartz; Planar deformation features; Siljan; Målingen; Hummeln;

    Sammanfattning : Impact cratering was once considered a rare geological process of no, or little, importance to the evolution of the Solar System and planet Earth. After more than 50 years of space exploration and the discovery of numerous (~190 as of October 2016) impact structures on Earth, this view has changed, and it is now clear that impact craters are in fact one of the most common morphological features on solid bodies in the Solar System. LÄS MER

  5. 4. Wood and fibre mechanics related to the thermomechanical pulping process

    Författare :Jan-Erik Berg; Per Engstrand; Per A. Gradin; Tomas Björkqvist; Mittuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustic emission; Chips; Compression tests; Defibration; Disc refiners; Energy consumption; Fibre structure; Force sensors; Fracture; Impact strength; Mathematical analysis; Moisture content; Picea abies; Refining; Stiffness degradation; Strains; Temperature; Thermomechanical pulping; Velocity; Chemical engineering; Kemiteknik;

    Sammanfattning : The main objective of this thesis was to improve the understanding of some aspects on wood and fibre mechanics related to conditions in the thermomechanical pulping process. Another objective was to measure the power distribution between the rotating plates in a refiner. LÄS MER

  7. 5. Estimating the Air-Water Gas Transfer Velocity during Low Wind Conditions

    Författare :Sam Fredriksson; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Air.sea gas exchange; Turbulence; Heat flux; Natural convection; Shear; Direct numerical simulations; Gas transfer velocity; IR; Flux-chambers;

    Sammanfattning : The abundances of atmospheric carbon dioxide, CO2, and methane, CH4, are increasing. These increases affect e.g., the global carbon cycle and the climate both regionally and globally. LÄS MER