Engineering Mechanics Commons^™

Generic Strategies To Implement Material Grading In Finite Element Methods For Isotropic And Anisotropic Materials, Ke Yu

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

We look at generic strategies to transfer material grading into finite element methods. Three strategies are proposed to transfer material grading into the finite element analysis. These strategies are node-centered, element-centered, and the definition of material grading through external functions. The process to achieve each strategy is stated, and examples are used to illustrate each strategy, and to compare them. The strategies are implemented in finite-deformation nonlinear elastic analysis.

Several examples are used to illustrate the implementation of each strategy for graded isotropic materials. For these examples, the results obtained from finite element models are compared with those obtained from …

Me-Em Enewsbrief, December 2011, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Me-Em Enewsbrief, September 2011, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Vibration-Based Health Monitoring Of Multiple-Stage Gear Train And Differential Planetary Transmission Involving Teeth Damage And Backlash Nonlinearity, Andrew Patrick Sommer

Master's Theses

The objective of this thesis is to develop vibration-based fault detection strategies for on-line condition monitoring of gear transmission systems. The study divides the thesis into three sections. First of all, the local stresses created by a root fatigue crack on a pinion spur gear are analyzed using a quasi-static finite element model and non-linear contact mechanics simulation. Backlash between gear teeth which is essential to provide better lubrication on tooth surfaces and to eliminate interference is included as a defect and a necessary part of transmission design. The second section is dedicated to fixed axis power trains. Torsional vibration …

Characterisation, Modelling And Simulation Of Flexible Polyurethane Foam, Conor Briody, Barry Duignan, Stephen Jerrams

Conference Papers

Flexible polyurethane foam is an open-celled polymeric material that exhibits strain rate and temperature effects. It has found various applications in areas including the packaging, medical, sports, aerospace and aeronautical industries. Polyurethane foam is ubiquitous in seating applications and finds particular use in specialised wheelchair seating where customised seating solutions are required which can provide proper comfort and support without the risk of developing pressure ulcers. Proper seating design is critical for users if this problem is to be avoided, but a lack of quantitative knowledge of this material’s behaviour has limited its effectiveness. The objectives of the work presented …

Me-Em Enewsbrief, June 2011, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Ultrasonic And Stereo-Optical Characterization Techniques For Applications In Mechanical Testing, Jonathan M. Hein

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

This thesis considers methods developed based on ultrasonic reflections from interfaces and stereo-optical surface strain measurements to study the mechanical characterization of materials and bodies. The ultrasonic method is used to characterize wave speed and attenuation for highly attenuating samples. The stereo-optical strain measurements are used to characterize the effects of genes on mechanical properties of bone, and the dynamic characterization of blast waves in the UNL Shock Wave Trauma Mechanics facility.

A method is described and developed for characterizing the wave speed and attenuation spectrums from reflected waves from the contact surface with an unknown material. The method is …

Me-Em Enewsbrief, March 2011, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Me-Em 2011 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

• ME-EM: 85 Years of Excellence
• Faculty & Staff
• Enrollment & Degrees
• Alumni
• Resources
• Graduates

Solving The Partial Differential Equation Of Vibrations With Interval Parameters Using The Interval Finite Difference Method, Brenda G. Medina

Open Access Theses & Dissertations

Accuracy and efficiency are among the main factors that drive today's innovative disciplines. As technology rapidly advances, efficiency takes on new meanings but what about accuracy? How accurate is accurate? Human error, uncertainties in measurement, and rounding errors are just some causes of inaccuracy. Interval Computations is an area that allows for such issues to be taken into account; for each measurement attained (for example), an interval can be built by considering the error associated with the measurement, and such an interval can be utilized in the mathematical computations of interest.

We consider the partial differential equation (PDE) of vibrations …

The Influence Of Pressure Relaxation On The Structure Of An Axial Vortex, Robert L. Ash, Irfan Zardadkhan, Allan J. Zuckerwar

Mechanical & Aerospace Engineering Faculty Publications

Governing equations including the effects of pressure relaxation have been utilized to study an incompressible, steady-state viscous axial vortex with specified far-field circulation. When sound generation is attributed to a velocity gradient tensor-pressure gradient product, the modified conservation of momentum equations that result yield an exact solution for a steady, incompressible axial vortex. The vortex velocity profile has been shown to closely approximate experimental vortex measurements in air and water over a wide range of circulation-based Reynolds numbers. The influence of temperature and humidity on the pressure relaxation coefficient in air has been examined using theoretical and empirical approaches, and …