Open Access. Powered by Scholars. Published by Universities.®
University of Nebraska - Lincoln
Department of Mechanical and Materials Engineering: Faculty Publications
- Keyword
-
- Axial conduction (2)
- Thermal entrance (2)
- Adhesion (1)
- Annular fin (1)
- Artery (1)
-
- Conjugate heat transfer (1)
- Contact conductance (1)
- Correlation (1)
- Finite element analysis (1)
- Finite element method (1)
- Green’s function (1)
- Heat transfer (1)
- Heat transfer coefficient (1)
- Interface (1)
- Lamina (1)
- Mass sensor (1)
- Moving boundary (1)
- Parameter estimation (1)
- Plaque (1)
- Plate (1)
- Ply (1)
- Resonator (1)
- Restenosis (1)
- Slug flow (1)
- Stent (1)
- Stress intensity factor (1)
- Stress transfer (1)
- Thickness shear (1)
Articles 1 - 8 of 8
Full-Text Articles in Engineering
The Relation Between The Arterial Stress And Restenosis Rate After Coronary Stenting, Linxia Gu, Shijia Zhao, Aswini K. Muttyam, James M. Hammel
The Relation Between The Arterial Stress And Restenosis Rate After Coronary Stenting, Linxia Gu, Shijia Zhao, Aswini K. Muttyam, James M. Hammel
Department of Mechanical and Materials Engineering: Faculty Publications
Two commercially available stents (the Palmaz–Schatz (PS) and S670 stents) with reported high and low restenosis rates, respectively, have been investigated in this paper. Finite element models simulating the stent, plaque, and artery interactions in 3 mm stenosed right coronary arteries were developed. These models were used to determine the stress field in artery walls after stent implantation. The material properties of porcine arteries were measured and implemented in the numerical models. The stress concentration induced in the artery by the PS stent was found to be more than double that of the S670 stent. It demonstrated a good correlation …
Steady-State Green’S Function Solution For Moving Media With Axial Conduction, A. Haji-Sheikh, J. V. Beck, Kevin D. Cole
Steady-State Green’S Function Solution For Moving Media With Axial Conduction, A. Haji-Sheikh, J. V. Beck, Kevin D. Cole
Department of Mechanical and Materials Engineering: Faculty Publications
The objective of this presentation is the development of a generalized steady-state Green’s function solution to study the temperature field in moving bodies. This type of solution permits the inclusion of different nonhomogeneous boundary conditions, volumetric heat sources, and possible position-dependent thermophysical properties. Although the mathematical formulation is for moving solids, it can be used to study the heat transfer in a moving fluid with a non-uniform velocity distribution passing through a micro-channel or fluid-saturated porous ducts. Additionally, this presentation includes the application of this Green’s function solution to acquire numerical information for selected examples to further illustrate the numerical …
Steady-Periodic Heating In Parallel-Plate Microchannel Flow With Participating Walls, Kevin D. Cole
Steady-Periodic Heating In Parallel-Plate Microchannel Flow With Participating Walls, Kevin D. Cole
Department of Mechanical and Materials Engineering: Faculty Publications
Simulations are presented for thermal sensing of steady laminar flow in a parallel-plate microchannel. Steady-periodic heating is introduced at the channel wall and temperatures are reported at upstream and downstream locations to represent temperature sensors. Exact analytical expressions for the temperature are given in the form of integrals, and numerical values are found by quadrature. Because axial conduction is prominent, there is a well-defined measurable flow range associated with each thermal-sensor geometry. Various fluid-flow rates, heating frequencies, sensor locations, and wall properties are explored. The results are given as a design correlation which shows the extent to which a given …
Finite Element Analysis Of Cracks In Aging Aircraft Structures With Bonded Composite-Patch Repairs, Linxia Gu, Ananth Ram Mahanth Kasavajhala, Shijia Zhao
Finite Element Analysis Of Cracks In Aging Aircraft Structures With Bonded Composite-Patch Repairs, Linxia Gu, Ananth Ram Mahanth Kasavajhala, Shijia Zhao
Department of Mechanical and Materials Engineering: Faculty Publications
Bonded composite-patch repair has been used to transfer load from cracked structures to the reinforcement such that subsequent crack propagation is reduced. In this study,the mechanical behavior of a single edge v-notch A17075-T6 plate repaired with 1-ply and 4-ply composite patches was investigated through the finite element method. Contour integral method was used to define and evaluate the stress intensity factors at the crack tip. The effect of the adhesive epoxy film, patch material, thickness and ply orientations on the evolution of the stress intensity factor (SIF) of the repaired structure was examined. The results indicated that the SIF of …
Thermal Models Of Railroad Wheels And Bearings, Kevin D. Cole, Constantine M. Tarawneh, Arturo A. Fuentes, B. M. Wilson, L. Navarro
Thermal Models Of Railroad Wheels And Bearings, Kevin D. Cole, Constantine M. Tarawneh, Arturo A. Fuentes, B. M. Wilson, L. Navarro
Department of Mechanical and Materials Engineering: Faculty Publications
The rolling surface for railroad wheels can be a heat source that may have an impact on the performance of the wheel bearing. In this study, experimental data from an electrically-heated railroad wheel set is analyzed by constructing thermal models of the wheel set. A steady finite-element model, a steady-analytical model, and a transient lumped-parameter model are discussed. Model parameters are determined from careful comparisons with the experimental data. The lumped-parameter model given here is intended as a simple predictive tool for determining when wheel heating caused by rail operations will have an impact on bearing temperature. The model parameters …
Luminescence Enhancement Of Cdte Nanostructures In Laf3:Ce/Cdte Nanocomposites, Mingzhen Yao, Xing Zhang, Lun Ma, Wei Chen, Alan G. Joly, Jinsong Huang, Qingwu Wang
Luminescence Enhancement Of Cdte Nanostructures In Laf3:Ce/Cdte Nanocomposites, Mingzhen Yao, Xing Zhang, Lun Ma, Wei Chen, Alan G. Joly, Jinsong Huang, Qingwu Wang
Department of Mechanical and Materials Engineering: Faculty Publications
Radiation detection demands new scintillators with high quantum efficiency, high energy resolution, and short luminescence lifetimes. Nanocomposites consisting of quantum dots and Ce3+ doped nanophosphors may be able to meet these requirements. Here, we report the luminescence enhancement of LaF3:Ce/CdTe nanocomposites which were synthesized by a wet chemistry method. CdTe quantum dots in LaF3:Ce/CdTe nanocomposites are converted into nanowires, while in LaF3 /CdTe nanocomposites no such conversion is observed. As a result, the CdTe luminescence in LaF3:Ce/CdTe nanocomposites is enhanced about five times, while in LaF3 /CdTe nanocomposites no enhancement was …
Directional Annealing-Induced Texture In Melt-Spun (Sm12Co88)99Nb1 Alloy, Tanjore V. Jayaraman, P. Rogge, Jeffrey E. Shield
Directional Annealing-Induced Texture In Melt-Spun (Sm12Co88)99Nb1 Alloy, Tanjore V. Jayaraman, P. Rogge, Jeffrey E. Shield
Department of Mechanical and Materials Engineering: Faculty Publications
Developing texture in nanocrystalline permanent magnet alloys is of significant importance. Directional annealing is shown to produce texture in the permanent magnet alloy (Sm12Co88)99Nb1. Melt spinning produced isotropic grain structures of the hard magnetic metastable SmCo7 phase, with grain sizes of ∼300 nm. Conventional annealing of melt-spun (Sm12Co88)99Nb1 alloy produced Sm2Co17 phase with random crystallographic orientation. Directional annealing of melt-spun (Sm12Co88)99Nb1 alloy, with appropriate combinations of annealing temperature and translational velocity, produced Sm2 …
Effects Of A Mass Layer With Gradually Varying Thickness On A Quartz Crystal Microbalance, Nan Liu, Jiashi Yang, Weiqiu Chen
Effects Of A Mass Layer With Gradually Varying Thickness On A Quartz Crystal Microbalance, Nan Liu, Jiashi Yang, Weiqiu Chen
Department of Mechanical and Materials Engineering: Faculty Publications
We study the effects of the nonuniform thickness of a thin mass layer on a quartz crystal microbalance. A theoretical analysis is performed on thickness-shear vibration of an AT-cut quartz plate with a nonuniform mass layer. Mindlin’s two-dimensional equation for thickness-shear vibration of a quartz plate is used. Free vibration frequencies and modes are obtained. The effects of the mass layer nonuniformity are examined. It is shown that resonant frequencies and energy trapping of thickness-shear modes are sensitive to mass layer nonuniformity.