Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1985. / Vita. Abstract. Includes bibliographical references (leaves 86-90). Also available via the Internet

Dissertation (Ph.D.) -- Worcester Polytechnic Institute. / Keywords: Turbulence; mixing length; vortical structure. Includes bibliographical references (p.).

Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references (leaves 31-33). Also available via the World Wide Web.

Thesis (M.S.E.)--University of Delaware, 2008. / Principal faculty advisor: James T. Kirby, Dept. of Civil & Environmental Engineering. Includes bibliographical references.

No description available.

published_or_final_version / Mechanical Engineering / Doctoral / Doctor of Philosophy

published_or_final_version / Mechanical Engineering / Doctoral / Doctor of Philosophy

We have studied the stationary solutions to the two-dimensional Euler's equation. A highly accurate scheme, based on boundary integral techniques was used in investigating these steady-state configurations. Bifurcation analysis on the solution of a uniform vortex patch in an externally applied strain field, yield new non-elliptical steady-state solutions apart from the elliptical structures reported by Moore & Saffman. The elliptical solutions correspond to the points on the primary solution branch and the non-elliptical solutions correspond to points on the bifurcation branches. We also observe the presence of a turning point indicating the finite resistance of these uniform vortices. Some of these new solutions suggest the possibility of coalescence between neighboring vortices. This leads to a new problem of considering a vortex pair in a strain field and computing their steady-state solutions. Numerical computations suggest that this guess is indeed correct, as we see the solution branch corresponding to the vortex pair intersect the bifurcation branch of the single vortex at a unique strain rate. Furthermore, looking at the profiles on the other bifurcation branches, it appears that merger of neighboring vortices is a recurring phenomenon.

An axially symmetric water jet was designed and constructed to complement an existing air jet facility. The water jet operates at Reynolds numbers, based on nozzle diameter, up to 50,000. The jet is forced at high levels by a reciprocating Scotch yoke mechanism. By using an output signal from the Scotch yoke as a phase reference, it is possible to obtain either phase-locked hot film data or phase-locked photographs of the dye-marked coherent vortical structures in the shear layer. By assuming zero azimuthal velocity, continuity allows reconstruction of the vorticity field from the data obtained traversing the jet using a single straight hot film probe. Thus the phase-locked photographs and the phase-locked data sets can be compared. The close agreement of the reconstructed vorticity with the photographs gives credence to the assumption of zero azimuthal velocity, and shows that the dye injection method of flow visualization accurately represents the vortical structure of this flow.

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Bibliography: leaves 381-382. / Sc.D.