AbstractsMathematics

Method of Riemann Surfaces in Modelling of Cavitating Flow

by Anna Zemlyanova




Institution: Louisiana State University
Department: Mathematics
Degree: PhD
Year: 2010
Keywords: cavitation; Riemann surface; Riemann-Hilbert problem; conformal mapping
Record ID: 1887787
Full text PDF: http://etd.lsu.edu/docs/available/etd-06182010-150903/


Abstract

This dissertation is concerned with the applications of the Riemann-Hilbert problem on a hyperelliptic Riemann surface to problems on supercavitating flows of a liquid around objects. For a two-dimensional steady irrotational flow of liquid it is possible to introduce a complex potential w(z) which allows to apply the powerful methods of complex analysis to the solution of fluid mechanics problems. In this work problems on supercavitating flows of a liquid around one or two wedges have been stated. The Tulin single-spiral-vortex model is employed as a cavity closure condition. The flow domain is transformed into an auxiliary domain with known boundaries using the conformal mapping method. After that the problems have been reduced to the solution of Riemann-Hilbert problems on elliptic or hyperelliptic Riemann surfaces. The final step is to solve a system of transcendental equations which is accomplished numerically. The numerical results are presented. To the best of the authors knowledge no numerical results were available for non-linear problems on supercavitating flows in multiply connected domains before.