Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.463267
Title: The design and development of spark light sources and their applications to visualisation of unsteady gas flow
Author: Lim, Lennie Enk Ng
ISNI:       0000 0001 3610 1258
Awarding Body: University of Surrey
Current Institution: University of Surrey
Date of Award: 1973
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Abstract:
This thesis reports on the various types of spark gaps designed for high speed repetitive operations. The environmental effects, upon which the performance of the spark gap depends, have been investigated. Present and past spark gaps have been tested and their suitability for repetitive work has also been assessed. The designs of the present spark gaps have been applied to the study of the rocket ignition process; the diaphragm opening process; the shock formation process and the shock wave propagation in discontinuous ducts. A simple theory for the diaphragm opening process, based on the freely hinged diaphragm with critical pressure being assumed behind the rupturing diaphragm just prior to opening has been developed. The results have been compared with those of the practical. The result of DREWRY & WALENTA /STD18/ (1965) has also been used for comparison. A graphical analysis has been developed for the shock formation process which assumes the actual (or linear) diaphragm opening history rather than the instantaneous rupture. It enables the shock formation distance and the shock formation time to be quickly determined given the initial conditions and the diaphragm opening history. Both the linear and the actual diaphragm histories have been used in the analysis. The work of SATOFUKA /STS22/ (1970) has also been used for comparison. A numerical technique capable of solving two-dimensional unsteady flow, known as the FLIC method, has been applied to the study of shock wave propagation in discontinuous ducts. Numerical results together with iso-density plots, wave diagrams and pressure histories have been obtained and compared with those of the practical.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.463267  DOI: Not available
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