The effect of vibration upon the rate of sublimation from horizontal circular cylinders has been studied previously in several investigations. However, no satisfactory overall correlation has been obtained up to the present time. In the present investigation, data have been obtained for mass transfer from naphthalene to air and phenol to air for horizontal cylinders vibrated vertically over a wide range of Reynolds number. It is shown that these data and the data of all previous investigations, including liquid systems, lie on or near a single smooth curve provided that an appropriate system of coordinates is selected. Further, for high Reynolds number and high Schmidt number, the data approach the theoretical equation of Jameson derived using boundary-layer theory. The author has found that the mass transfer coefficient for sublimation can be increased by a factor of 30 over that which prevails for the stationary (non-vibrating) case. For mass transfer to gaseous media only, the following correlation is proposed, having an average deviation of ±17 % : Sh = 0.261 Sc¹/³Revº•⁷¹⁷( H/d )º•²³³ This equation is believed to be valid over the following range of the variables: Diameter: 0.07 - 1.1 cm Frequency: 100 - 7000 RPM Amplitude (double): 0.05 - 4.0 cm Vibrational Reynolds number: 9 - 2000 Ratio of amplitude to diameter: 0.2 - 5.7 / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

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xii, 207 leaves : ill., photos., graphs, tables ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1979) from the Dept. of Mechanical Engineering, University of Adelaide

Note: / This thesis deals with flow-induced ovalling oscillation and the mechanical characteristics of cylindrical shells. The experiments were conducted with epoxy shells which were either clamped at both ends or clamped at one end and free at the other end. The response of the shells in cross flow was studied in a wind tunnel. A mini-shaker and a fotonic sensor were used to determine the mechanical characteristics (including the natural frequencies, modal damping, and the axial and circumferentia1 mode shapes) of the shells. An analytical method was developed, with the use of potential flow theory for the aerodynamic force, to calculate the oscillation frequencies as well as the negative aerodynamic damping values of clamped-clamped shells. Theory and experiments prove that flow-induced ovalling vibration of a cylindrical shell is not a three-dimensional effect, but rather an aeroelastic phenomenon. Vibration of the shell does not depend on flow periodicity in the wakes and an integral relationship (f/fvs) between the shell frequency (f) and the vortex shedding frequency (fvs) is not necessary at the onset of ovalling. / Cette these traite des oscillations induites par ecoulements, incluant les characteristiques mecaniques de coques cylindriques. Un mini-vibrateur et un capteur optique (Fotonic) ont ete utilises pour determiner les characteristiques mecaniques (inc1uant les frequences naturelles: l'amortissement, et les formes modales axiales et circonferentielles) des coques. Une methode analytique a ete developpee pour le calcul des frequences d'oscillations, ainsi que les valeurs negatives de l'amortissement aerodynamique des coques fixes, faisant usage de la theorie des ecoulements potentiels pour les forces aerodynamiques. La theorie et les essais sur ces coques demontrent que la vibration induite par ecoulements est un phenomene aeroelastique bi-dimensionnel, plutot que tri-dimensionnel. Les vibrations de la coque ne dependent pas de la periodicite de ecoulement dans le sillage, et un rapport integral (f/f ) vs entre la frequence de la coque et la frequence du detachement de tourbillons n'existe pas necessairement, au seuil des vibrations.

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