Date of Award

1-1-2017

Document Type

Dissertation

Degree Name

Ph.D.

Department

Engineering

First Advisor

Yun-Bo Yi, Ph.D.

Second Advisor

Maria Calbi

Keywords

Thermomechanical Stability, Clutches, Brakes, Automotive

Abstract

Finite element analyses were performed to evaluate the stability thermal buckling existing in clutch disks. The commercial software ABAQUS had been used. It was discovered that monotonically increasing thermal loads constantly result in axisymmetric buckling modes. When the maximum values of thermal loads were located at the medium radii of the models, the non-axisymmetric modes became dominant. The buckling mode and buckling temperature of the model in which the profile of thermal load varies periodically in the circumferential direction were also tentatively studied. The achievments described in this part of this dissertation had been published in Ref. [33].

The numerical analysis was applied to inspect the thermal buckling of an annular plate using a reduced Fourier method. The stress stiffness matrix was derived from the geometric nonlinearity in the Green strains with a predefined circumferential wave number. It was implemented to solve non-axisymmetric problems with multiple reversals in the circumferential direction. It was shown that there exists a particular wave number with which the buckling temperature reaches a minimum. The achievments described in this part of this dissertation had been published in Ref. [58].

Through performing finite element analyses, the coupling between thermal buckling and thermoelastic instability (TEI) was studied. The eigenmodes (i.e. nodal temperature distributions) obtained from TEI analyses were applied as the reference thermal loads. The effects of the sliding speed, the coefficient of friction, and the boundary condition had been investigated. It was concluded that TEI and thermal buckling could interact with each other in some situations. The achievments described in this part of this dissertation will be published in Ref. [63].

Linear and nonlinear buckling finite element analyses were performed to evaluate the thermal postbuckling of clutch metal disks. The dominant buckling modes were firstly obtained through linear buckling FEA analyses. The scaled displacement fields obtained from the linear buckling analyses were applied to the original geometries to produce the perturbed meshes. The postbuckling behaviors were then investigated through nonlinear buckling FEA analyses. The software ABAQUS was used as the fundamental numerical tool. It was discovered the temperature dependence of material properties significantly decreases the cirtical buckling. The achievments described in this part of this dissertation will be published in Ref. [72].

Copyright Statement / License for Reuse

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Provenance

Received from ProQuest

Rights holder

Zhuo Chen

File size

140 p.

File format

application/pdf

Language

en

Discipline

Mechanical engineering

Available for download on Saturday, September 21, 2019

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