Now showing items 20-39 of 53 starting with H

    • A highly adaptive three dimensional hybrid vortex method for inviscid flows and helically symmetric vortex equilibria 

      Lucas, Daniel (University of St Andrews, 2012-06-22) - Thesis
      This thesis is concerned with three-dimensional vortex dynamics, in particular the modelling of vortex structures in an inviscid context. We are motivated by the open problem of regularity of the inviscid equations, i.e. ...
    • Inhomogeneous magnetic fields in the solar atmosphere 

      Browning, Philippa (University of St Andrews, 1984) - Thesis
      The magnetic field in the solar atmosphere is highly inhomogeneous. In the photosphere, the field is concentrated into intense flux tubes and the coronal magnetic field consists of many loops and regions of open field. ...
    • An investigation into the use of balance in operational numerical weather prediction 

      Devlin, David J. J. (University of St Andrews, 2011) - Thesis
      Presented in this study is a wide-ranging investigation into the use of properties of balance in an operational numerical weather prediction context. Initially, a joint numerical and observational study is undertaken. ...
    • The investigation of quasi-separatrix layers in solar magnetic fields 

      Restante, Anna Lisa (University of St Andrews, 2011-06-20) - Thesis
      The structure of the magnetic field is often an important factor in many energetic processes in the solar corona. To determine the topology of the magnetic field features such as null points, separatrix surfaces, and ...
    • Magnetic flux transport simulations : applications to solar and stellar magnetic fields 

      Cook, Graeme Robert (University of St Andrews, 2011-11) - Thesis
      Magnetic fields play a key role in a wide variety of phenomena found on the Sun. One such phenomena is the Coronal Mass Ejection (CME) where a large amount of material is ejected from the Sun. CME’s may directly affect ...
    • Magnetic skeletons and 3D magnetic reconnection 

      Haynes, Andrew L. (University of St Andrews, 2008-06-23) - Thesis
      The upper atmosphere of the sun, the solar corona, is approximately 1,000,000K hotter than the surface of the Sun, a property which cannot be explained by the normal processes of heat conduction and radiation. It is now ...
    • MHD evolution of magnetic null points to static equilibria 

      Fuentes Fernández, Jorge (University of St Andrews, 2011-05-18) - Thesis
      In magnetised plasmas, magnetic reconnection is the process of magnetic field merging and recombination through which considerable amounts of magnetic energy may be converted into other forms of energy. Reconnection is a ...
    • MHD mode conversion of fast and slow magnetoacoustic waves in the solar corona 

      McDougall-Bagnall, A. M. Dee (University of St Andrews, 2010-11-30) - Thesis
      There are three main wave types present in the Sun’s atmosphere: Alfvén waves and fast and slow magnetoacoustic waves. Alfvén waves are purely magnetic and would not exist if it was not for the Sun’s magnetic field. The ...
    • MHD simulations of coronal heating 

      Tam, Kuan V. (University of St Andrews, 2014-12-01) - Thesis
      The problem of heating the solar corona requires the conversion of magnetic energy into thermal energy. Presently, there are two promising mechanisms for heating the solar corona: wave heating and nanoflare heating. In ...
    • Modelling chromospheric evaporation in response to coronal heating 

      Johnston, Craig David (University of St Andrews, 2018-06-26) - Thesis
      This thesis presents a new computationally efficient method for modelling the response of the solar corona to the release of energy. During impulsive heating events, the coronal temperature increases which leads to a ...
    • New aspects of particle acceleration in collapsing magnetic traps 

      Eradat Oskoui, Solmaz (University of St Andrews, 2014-01) - Thesis
      Collapsing magnetic traps (CMTs) have been suggested as one of the mechanisms that could contribute to particle energisation in solar flares. The basic idea behind CMTs is that charged particles will be trapped on the ...
    • A non-linear force-free field model for the solar magnetic carpet 

      Meyer, Karen Alison (University of St Andrews, 2012-06-22) - Thesis
      The magnetic carpet is defined to be the small-scale photospheric magnetic field of the quiet Sun. Observations of the magnetic carpet show it to be highly dynamic, where the time taken for all flux within the magnetic ...
    • Numerical modelling of two HMX-based plastic-bonded explosives at the mesoscale 

      Handley, Caroline A. (University of St Andrews, 2011-06-22) - Thesis
      Mesoscale models are needed to predict the effect of changes to the microstructure of plastic-bonded explosives on their shock initiation and detonation behaviour. This thesis describes the considerable progress that has ...
    • Numerical modelling of ultra low frequency waves in Earth's magnetosphere 

      Elsden, Tom (University of St Andrews, 2016-06-24) - Thesis
      Ultra Low Frequency (ULF) waves are a ubiquitous feature of Earth's outer atmosphere, known as the magnetosphere, having been observed on the ground for almost two centuries, and in space over the last 50 years. These waves ...
    • Numerical simulations of footpoint driven coronal heating 

      O'Hara, Jennifer (University of St Andrews, 2016-06-24) - Thesis
      Magnetic field permeates the solar atmosphere and plays a crucial role in the dynamics, energetics and structures observed. In particular, magnetic flux tubes provide the structure for coronal loops that extend from the ...
    • Numerical simulations of sunspot rotation driven by magnetic flux emergence 

      Sturrock, Zoe (University of St Andrews, 2017-06-23) - Thesis
      Magnetic flux continually emerges from the Sun, rising through the solar interior, emerging at the photosphere in the form of sunspots and expanding into the atmosphere. Observations of sunspot rotations have been reported ...
    • On the properties of single-separator MHS equilibria and the nature of separator reconnection 

      Stevenson, Julie E. H. (University of St Andrews, 2015-06-26) - Thesis
      This thesis considers the properties of MHS equilibria formed through non-resistive MHD relaxation of analytical non-potential magnetic field models, which contain two null points connected by a generic separator. Four ...
    • On the theory of symmetric MHD equilibria with anisotropic pressure 

      Hodgson, Jonathan David Brockie (University of St Andrews, 2016) - Thesis
      In this thesis we discuss the theory of symmetric MHD equilibria with anisotropic pressure. More specifically, we focus on gyrotropic pressures, where the pressure tensor can be split into components along and across the ...
    • On the topology of global coronal magnetic fields 

      Edwards, Sarah J. (University of St Andrews, 2014-12-01) - Thesis
      This thesis considers the magnetic topology of the global solar corona. To understand the magnetic topology we use the magnetic skeleton which provides us with a robust description of the magnetic field. To do this we use ...
    • The origin and dynamic interaction of solar magnetic fields 

      Wilmot-Smith, A.L. (University of St Andrews, 2008-06) - Thesis
      The dynamics of the solar corona are dominated by the magnetic field which creates its structure. The magnetic field in most of the corona is ‘frozen’ to the plasma very effectively. The exception is in small localised ...