Thesis (M.S.)--Rutgers University, 2007. / "Graduate Program in Mechanical and Aerospace Engineering." Includes bibliographical references (p. 144-146).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 47-50). Also available via the Internet.

Thesis (doctoral)--Technische Universiteit Delft, 1997. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Lehigh University, 2005. / Includes vita. Includes bibliographical references (leaves 219-223).

Thesis (Ph. D.)--Lehigh University, 2006. / Includes vita. Includes bibliographical references (leaves 173-177).

Current manufacturing research aims at increasing productivity by optimal selection of process parameters. This is accomplished by understanding the fundamental physics of individual manufacturing processes. In this thesis, peripheral milling of very flexible cantilevered plates is studied. The static and dynamic deflections of the plate under periodic milling forces are modelled. A new dynamic cutting force model is developed which considers five discrete zones of relative motion between the tool and the workpiece. The kinematics of both milling and vibratory motions are modelled, which is an original research contribution in this area. It is shown that the penetration of the tool into the workpiece during vibratory cutting has a strong influence on the damping and stiffness characteristics of the milling process. A structural model of a discontinuous cantilevered plate is determined using the finite element method. A reduced order structural model at the tool-workpiece contact zone is implemented for discrete time response analysis of the plate under cutting force excitations during milling. The closed loop dynamic behaviour of the system is modelled and taken into account in the analysis. Simulations of plate machining are compared with experimental results. A model of the surface finish generation mechanism is deduced from the analysis and experimental results. Applications of this research include peripheral milling of integral jet engine impellers, computer disk drives and other flexible mechanical components. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

<p>A crush test fixture for measuring energy absorption of flat plate specimens from an earlier study was redesigned to eliminate the problem of binding of the load transfer platen with the guide posts. Further modifications were to increase the stroke, and combine the two scaled test fixtures into one. This new crush test fixture was shown to produce load displacement histories exhibiting well developed sustained crushing loads over long strokes.</p> <p> An experimental study was conducted on two material systems: AS4/3502 graphite/epoxy, and a hybrid AS4-Kevlar/3502 composite. The effect of geometric scaling of specimen size, the effect of ply-level and sublaminate-Ievel scaling of the stacking sequence of the full scale specimens, and the effect of trigger mechanism on the energy absorption capability were investigated.</p> <p> The new crush test fixture and flat plate specimens produced peak and sustained crushing loads that were lower than obtained with the old crush test fixture. The trigger mechanism used influenced the specific sustained crushing stress (SSCS). The results of this study indicated that to avoid any reduction in the SSCS when scaling from the 1/2 scale to full scale specimen size, the sublaminate-level scaling approach should be used, in agreement with experiments on tubes. The use of Kevlar in place of the graphite 45° plies was not as effective a means for supporting and containing the 0° graphite plies for crushing of flat plates and resulted in a drop in the SSCS. This result did not correlate with that obtained for tubes.</p> / Master of Science

Heat transfer in turbulent flow from external surfaces has been investigated extensively in the past. Most of the theoretical and experimental work deals with a two dimensional boundary layer on isothermal or uniform heat flux surfaces with longitudinal temperature variation. However, little attention has ever been paid to the case in which the temperature of the plate varies transversely. This is a three dimensional problem due to the spanwise variation of the thermal boundary layer. The most elementary example of this is the boundary formed by the sudden temperature impulse that acts transversely across a flat plate as shown in Fig. 1. Theoretically, this spanwise boundary increases the heat transfer coefficient. A knowledge of this is important in the field of heating and cooling system design. It is also important for the investigation of spot-heat flux measurement.

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