Sökning: "Maskinteknik Rymd- och flygteknik"

Visar resultat 11 - 15 av 156 avhandlingar innehållade orden Maskinteknik Rymd- och flygteknik.

  1. 11. Turbulence-resolving simulations for engineering applications

    Författare :Bastian Nebenführ; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Aeroacoustics; Forest canopy; Airframe noise; hybrid RANS LES; Turbulence-resolving simulation; Wind-turbine fatigue loads; Wind power;

    Sammanfattning : Most fluid flows of industrial interest are turbulent and their accurate representation may be of vital importance for the design process of new products. To date, steady RANS methods are usually employed for the simulation of turbulent flows of everyday engineering problems. LÄS MER

  3. 12. Bio-inspired retinal optic flow perception in robotic navigation

    Författare :Björnborg Nguyen; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; robotic navigation; active fixation; visual perception; bionics; Retinal optic flow fields; gazing; optic flow; retinal flow path;

    Sammanfattning : This thesis concerns the bio-inspired visual perception of motion with emphasis on locomotion targeting robotic systems. By continuously registering moving visual features in the human retina, a sensation of a visual flow cue is created. An interpretation of visual flow cues forms a low-level motion perception more known as retinal optic flow. LÄS MER

  4. 13. Large-eddy simulation on the effects of fuel injection pressure on gasoline spray characteristics

    Författare :Sandip Wadekar; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High pressure fuel-injection; GDI engine; LES; Spray characteristics;

    Sammanfattning : Increasing the injection pressure in gasoline direct injection engines has a substantial potential to reduce emissions while maintaining high efficiency in spark ignition engines. Present gasoline injectors operate at pressures of 20 to 30 MPa. LÄS MER

  5. 14. Cavity Purge Flows in High Pressure Turbines

    Författare :Johan Dahlqvist; Björn Laumert; Jens Fridh; Paul Beard; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbomachinery; axial turbine; cavity purge; purge flow; wheelspace; rim seal; spanwise transport; radial transport; effectiveness; cooling; efficiency; strömningsmaskiner; axialturbin; kavitetsrensningsflöde; kavitetsflöde; tätkant; spännviddsvis transport; radiell transport; effektivitet; kylning; verkningsgrad; Energy Technology; Energiteknik;

    Sammanfattning : Turbomachinery forms the principal prime mover in the energy and aviation industries. Due to its size, improvements to this fleet of machines have the potential of significant impact on global emissions. LÄS MER

  7. 15. Optimization of Vehicle Structures under Uncertainties

    Författare :Sandeep Shetty; Larsgunnar Nilsson; Kaj Fredin; Alexander Govik; Mårten Olsson; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Advancements in simulation tools and computer power have made it possible to incorporate simulation-based structural optimization in the automotive product development process. However, deterministic optimization without considering uncertainties such as variations in material properties, geometry or loading conditions might result in unreliable optimum designs. LÄS MER