Sökning: "Flyg- och rymdteknik"

Visar resultat 1 - 5 av 25 avhandlingar innehållade orden Flyg- och rymdteknik.

  1. 1. Improving Fixed Wing UAV Endurance, by Cooperative Autonomous Soaring

    Författare :Klas Andersson; Petter Ögren; Fredrik Bruhn; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; UAV; Autonomous soaring; Cooperative soaring; Computer Science; Datalogi; Flyg- och rymdteknik; Aerospace Engineering;

    Sammanfattning : The ever-expanding use and development of smaller UAVs (Unmanned Aerial Vehicles) has highlighted an increasing demand for extended range and endurance for this type of vehicles. In this thesis, the development of a concept and system for autonomous soaring of cooperating unmanned aerial vehicles is presented. LÄS MER

  2. 2. Assessment of Aircraft Radar Cross-Section for Detection Analysis

    Författare :Björn Persson; Ulf Ringertz; Martin Norsell; Peter Bull; João Tasso de Figueiredo Borges de Sousa; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flyg- och rymdteknik; Aerospace Engineering; Försvarssystem;

    Sammanfattning : Hiding from and surprising an opponent are tactics that have been used in warfare throughout history. They were features that aircraft originally possessed when they were first used in military operations. However, development of military technology is an endless struggle between advances in technology and counter technology. LÄS MER

  3. 3. 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

  4. 4. Wings, turbulent boundary layers and flow separation

    Författare :Fermin Mallor; Philipp Schlatter; Ricardo Vinuesa; Ramis Örlü; Manuel García Villalba; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wings; turbulent boundary layers; adverse pressure gradients; flow separation; numerical simulations; wind-tunnel experiments; flow control.; Vingar; turbulenta gränsskikt; negativa tryckgradienter; avlösning; numeriska simuleringar; vindtunnel-experiment; flow control; Aerospace Engineering; Flyg- och rymdteknik; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : The present doctoral thesis investigates the turbulent flow developing around wing sections, focusing on the impact of adverse-pressure-gradient (APG) conditions on turbulent boundary layers (TBLs) and the physics of flow separation. Both experimental and numerical methods are employed to generate high-fidelity data sets and provide an in-depth analysis of the flow. LÄS MER

  5. 5. Enhanced Composite Joint Performance through Interlacement of Metal Inserts

    Författare :Sahar Akbarpour; Stefan Hallström; Conor McCarthy; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aerospace Engineering; Flyg- och rymdteknik;

    Sammanfattning : The work in this thesis investigates bolted joints in fibre reinforced composites with particular focus on a novel insert concept. The concept is characterised by replacing all composite plies with stacked metal patches, locally around a bolt hole, so that they jointly form a solid metal reinforcement. LÄS MER