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Full-Text Articles in Mechanical Engineering
Cerebrospinal Fluid Dynamics In The Cervical Spine: Importance Of Fine Anatomical Structures, S. Pahlavian, T. Yiallourou, R. Tubbs, A. Bunck, M. Goodin, Francis Loth, M. Raisee, Bryn Martin
Cerebrospinal Fluid Dynamics In The Cervical Spine: Importance Of Fine Anatomical Structures, S. Pahlavian, T. Yiallourou, R. Tubbs, A. Bunck, M. Goodin, Francis Loth, M. Raisee, Bryn Martin
Dr. Bryn Martin
No abstract provided.
Acoustic And Dynamic Characteristics Of A Complex Urban Turnout Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen
Acoustic And Dynamic Characteristics Of A Complex Urban Turnout Using Fibre-Reinforced Foamed Urethane (Ffu) Bearers, Sakdirat Kaewunruen
Sakdirat Kaewunruen
A special track system used to divert a train to other directions or other tracks is generally called ‘railway turnout’. A traditional turnout system includes rails, switches, crossings (special track components), steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints …
Impact Mechanics And High-Energy Absorbing Materials: Review, Pizhong Qiao, Mijia Yang, Florin Bobaru
Impact Mechanics And High-Energy Absorbing Materials: Review, Pizhong Qiao, Mijia Yang, Florin Bobaru
Florin Bobaru Ph.D.
In this paper a review of impact mechanics and high-energy absorbing materials is presented. We review different theoretical models (rigid-body dynamics, elastic, shock, and plastic wave propagation, and nonclassical or nonlocal models. and computational methods (finite-element, finite-difference, and mesh-free methods. used in impact mechanics. Some recent developments in numerical simulation of impact (e.g., peridynamics) and new design concepts proposed as high energy absorbing materials (lattice and truss structures, hybrid sandwich composites, metal foams, magnetorheological fluids, porous shape memory alloys. are discussed. Recent studies on experimental evaluation and constitutive modeling of strain rate-dependent polymer matrix composites are also presented. Impact damage …
Rotor Crack Detection Using Active Magnetic Bearings, Jerzy Sawicki
Rotor Crack Detection Using Active Magnetic Bearings, Jerzy Sawicki
Jerzy T. Sawicki
Well-established procedures exist to monitor and diagnose fairly severe problems with rotating machinery but little progress has been made in developing techniques to detect subtle changes in machine condition for both improved diagnostics, and to develop prognostic procedures for determining remaining service life. Of all machine faults, crack initiated problems present probably the most significant safety and loss hazard in modern turbomachinery, including aircraft engines and power generation units. Different approaches are used to model, detect, and localize crack-induced damage in rotating structures. This paper presents novel application of active magnetic bearings (AMBs) for on-line rotor crack detection. AMB-actuators provide …
Dynamic Properties Of Railway Track And Its Components : A State-Of-The-Art Review, Sakdirat Kaewunruen, Alexander Remennikov
Dynamic Properties Of Railway Track And Its Components : A State-Of-The-Art Review, Sakdirat Kaewunruen, Alexander Remennikov
Alex Remennikov
Recent findings indicate one of major causes of damages, which is attributed to the resonant behaviours, in a railway track and its components. Basically, when a railway track is excited to generalised dynamic loading, the railway track deforms and then vibrates for certain duration. Dynamic responses of the railway track and its components are the key to evaluate the structural capacity of railway track and its components. If a dynamic loading resonates the railway track’s dynamic responses, its components tend to have the significant damage from excessive dynamic stresses. For example, a rail vibration could lead to defects in rails …
A Fully Lagrangian Numerical Method For Calculating The Dynamics Of Oscillating Micro And Nanoscale Objects Immersed In Fluid, Nicole N. Hashemi, Mark Paul, Javier Alcazar, Raul Radovitzky
A Fully Lagrangian Numerical Method For Calculating The Dynamics Of Oscillating Micro And Nanoscale Objects Immersed In Fluid, Nicole N. Hashemi, Mark Paul, Javier Alcazar, Raul Radovitzky
Nastaran Hashemi
Many micro and nano-technologies rely upon the complicated motion of objects immersed in a viscous fluid. It is often the case that for such problems analytical theory is not available to quantitatively describe and predict the device dynamics. In addition, the numerical simulation of such devices involves moving boundaries and use of the standard Eulerian computational approaches are often difficult to implement. In order to address this problem we use and validate a fully Lagrangian finite element approach that treats the moving boundaries in a natural manner. We validate the method for use in calculating the dynamics of oscillating objects …
An Experimental Study Of Molten Microdroplet Surface Deposition And Solidification: Transient Behavior And Wetting Angle Dynamics, Daniel Attinger, Z. Zhao, D. Poulikakos
An Experimental Study Of Molten Microdroplet Surface Deposition And Solidification: Transient Behavior And Wetting Angle Dynamics, Daniel Attinger, Z. Zhao, D. Poulikakos
Daniel Attinger
The basic problem of the impact and solidification of molten droplets on a substrate is of central importance to a host of processes. An important and novel such process in the area of micromanufacturing is solder jetting where microscopic solder droplets are dispensed for the attachment of microelectronic components. Despite the recent appearance of a few numerical studies focusing on the complex transient aspects of this process, no analogous experimental results have been reported to date to the best of our knowledge. Such a study is reported in this paper. Eutectic solder (63Sn37Pb) was melted to a preset superheat and …