Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638304
Title: A one dimensional analysis of singularities of the d-dimensional stochastic Burgers equation
Author: Neate, A. D.
Awarding Body: University of Wales Swansea
Current Institution: Swansea University
Date of Award: 2005
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Abstract:
This thesis presents a one dimensional analysis of the singularities of the d-dimensional stochastic Burgers equation using the ‘reduced action function’. In particular, we investigate the geometry of the caustic, the Maxwell set and the Hamliton-Jacobi level surfaces, and describe some turbulent phenomena. Chapter 1 begins by introducing the stochastic Burgers equation and its related Stratonovich heat equation. Some earlier geometric results of Davies, Truman and Zhao are presented together with the derivation of the reduced action function. In Chapter 2 we present a complete analysis of the caustic in terms of the derivatives of the reduced action function, which leads to a new method for identifying the singular (cool) parts of the caustic. Chapter 3 investigates the spontaneous formation of swallowtails on the caustic and Hamilton-Jacobi level surfaces. Using a circle of ideas due to Arnol’d, Cayley and Klein, we find necessary conditions for these swallowtail perestroikas and relate these conditions to the reduced action function. In Chapter 4 we find an explicit formula for the Maxwell set by considering the double points of the level surfaces in the two dimensional polynomial case. We extend this to higher dimensions using a double discriminant of the reduced action function and then consider the geometric properties of the Maxwell set in terms of the pre-Maxwell set. We conclude in Chapter 5 by using our earlier work to model turbulence in the Burgers fluid. We show that the number of cusps on the level surfaces can change infinitely rapidly causing ‘real turbulence’ and also that the number of swallowtails on the caustic can change infinitely rapidly causing ‘complex turbulence’. These processes are both inherently stochastic in nature. We determine their intermittence in terms of the recurrent behaviour of two processes derived from the reduced action.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.638304  DOI: Not available
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