Sökning: "Aerodynamic models"

Visar resultat 21 - 25 av 76 avhandlingar innehållade orden Aerodynamic models.

  1. 21. Aerodynamics simulations of ground vehicles in unsteady crosswind

    Författare :Tristan Favre; Gunilla Efraimsson; Michael Leschziner; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Detached-Eddy Simulations; Crosswind; Aerodynamics; ;

    Sammanfattning : Ground vehicles, both on roads or on rail, are sensitive to crosswinds and the handling, travelling speeds or in some cases, safety can be affected. Full modelling of the crosswind stability of a vehicle is a demanding task as the nature of the disturbance, the wind gust, is complex and the aerodynamics, vehicle dynamics and driver reactions interact with each other. LÄS MER

  3. 22. The Influence of Flow Leakage Modelling on Turbomachinery Blade Forcing Predictions

    Författare :Tobias Gezork; Björn Laumert; Paul Petrie-Repar; Damian Vogt; Mehdi Vahdati; KTH; []
    Nyckelord :Energiteknik; Energy Technology;

    Sammanfattning : Vibrations in turbomachinery engine components are undesirable as they put the structural integrity of the components at risk and can lead to failure during the lifetime of the turbomachinery engine. Vibrations arising from aerodynamic forces and stability of turbomachinery blades is assessed in the discipline of aeromechanics. LÄS MER

  4. 23. Aerodynamics of an Aeroengine Intermediate Compressor Duct: Effects from an Integrated Bleed System

    Författare :Elias Siggeirsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Intermediate Compressor Duct; S-shaped duct; DDES; Hybrid RANS LES; Dual-time-stepping; Bleed system; rotor off-take; SBES; CFD; Turbomachinery;

    Sammanfattning : With the successful development of high-bypass-ratio turbofan engines, major aerodynamic components have been optimized and continuous efficiency improvements are getting harder to maintain. Therefore, to meet the requirements of lower emission of greenhouse gases, auxiliary modules such as intermediate ducts are receiving increasing interest. LÄS MER

  5. 24. Power and Wake Dynamics of Hawkmoth Flight

    Författare :Kajsa Warfvinge; Evolutionär ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Insect flight; Aerodynamics; Wind tunnel; Particle Image Velocimetry PIV .; tomo-PIV; Power; Manduca sexta; Macroglossum stellatarum; Hawkmoth;

    Sammanfattning : Aerodynamic theory states that the power required to fly is related to flight speed with a ∪-shaped curve. This has been shown in vertebrates, but insects have been proposed to have a flat, or J-shaped power curve. LÄS MER

  7. 25. Numerical Methods for Turbomachinery Aeromechanical Predictions

    Författare :Maria Angelica Mayorca; Damian Vogt; Torsten Fransson; Robert Kielb; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aeromechanics; numerical tools; methods; turbomachinery; aeroelasticity; gas turbines; vibrations;

    Sammanfattning : In both aviation and power generation, gas turbines are used as key components. An important driver of technological advance in gas turbines is the race towards environmentally friendly machines, decreasing the fuel burn, community noise and NOx emissions. LÄS MER