Sökning: "Space Physics"

Visar resultat 26 - 30 av 638 avhandlingar innehållade orden Space Physics.

  1. 26. Realistic simulations of delta wing aerodynamics using novel CFD methods

    Författare :Stefan Görtz; Arthur Rizzi; Miguel Visbal; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; CFD; aerodynamics; flow physics; steady; unsteady; delta wing; vortical flow; Rymd- och plasmafysik; Space physics; Rymdfysik;

    Sammanfattning : The overall goal of the research presented in this thesis is to extend the physical understanding of the unsteady external aerodynamics associated with highly maneuverable delta-wing aircraft by using and developing novel, more efficient computational fluid dynamics (CFD) tools. More specific, the main purpose is to simulate and better understand the basic fluid phenomena, such as vortex breakdown, that limit the performance of delta-wing aircraft. LÄS MER

  3. 27. Gravitational perturbations in plasmas and cosmology

    Författare :Mats Forsberg; Gert Brodin; Michael Bradley; Christopher Clarkson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; general relativity; cosmology; gravitational waves; plasma; electromagnetic waves; nonlinear waves; Plasma physics; Plasmafysik; Theory of relativity; gravitation; Relativitetsteori; gravitation; Cosmology; Kosmologi; teoretisk fysik; Theoretical Physics;

    Sammanfattning : Gravitational perturbations can be in the form of scalars, vectors or tensors. This thesis focuses on the evolution of scalar perturbations in cosmology, and interactions between tensor perturbations, in the form of gravitational waves, and plasma waves. LÄS MER

  4. 28. Hubble Space Telescope Spectroscopy of Eta Carinae and Chi Lupi

    Författare :Torgil Zethson; Partikel- och kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetic and optical properties; supraconductors; electrical; Rymdteknik; kosmisk kemi; Condensed matter:electronic structure; rymdvetenskap; Astronomi; cosmic chemistry; space research; Astronomy; boron; isotope shifts; Chi Lupi; fluorescence; element abundances; emission lines; GHRS; strontium; STIS; Eta Carinae; spectroscopy; Hubble Space Telescope; supraledare; magnetiska och optiska ; magnetisk resonans; Space technology; spektroskopi; relaxation; magnetic resonance; egenskaper elektriska ; Kondenserade materiens egenskaper:elektronstruktur;

    Sammanfattning : Eta Carinae is a super-massive, super-luminous star. It is surrounded by a bipolar nebula, the "Homunculus", and several blobs of ejected gas which are the source of a complex emission-line spectrum. LÄS MER

  5. 29. Defect properties in dilute tungsten alloys from first-principles calculations

    Författare :Leili Gharaee; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; irradiation; structural materials; first-principles calculations.; point defects; tungsten alloys;

    Sammanfattning : .... LÄS MER

  7. 30. Cryogenic InP High Electron Mobility Transistors in a Magnetic Field

    Författare :Isabel Harrysson Rodrigues; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; magnetic field; cryogenic; low noise amplifier; angular dependence; InP HEMT; geometrical magnetoresistance;

    Sammanfattning : The InGaAs-InAlAs-InP high electron mobility transistor (InP HEMT) is the preferred active device used in a cryogenic low noise amplifier (LNA) for sensitive detection of microwave signals. In this thesis it is demonstrated that the InP HEMT, when placed in a magnetic field, has a strong angular dependence in its output current. LÄS MER