Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Alternating (1)
- Aluminium (1)
- Chemical reactions (1)
- Cohesive element (1)
- Compression after impact (1)
-
- Convection and radiation (1)
- Crack initiation (1)
- DNA (1)
- Damage accumulation (1)
- Damage progression (1)
- Delamination (1)
- Dielectrophoresis (1)
- Electric currents (1)
- Electric double layer (1)
- Electric fields (1)
- Electric power production – Equipment and supplies – Testing (1)
- Electro-osmosis (1)
- Electrochemistry (1)
- Electrostatics (1)
- Engineering structures (1)
- Fatigue and fracture (1)
- Finite element analysis (1)
- Fused salts (1)
- Growth and branching (1)
- Hydrodynamics (1)
- Hydrophobic surfaces (1)
- Impact (1)
- Impact damage (1)
- Microfluidics (1)
- Mirrors (1)
Articles 1 - 9 of 9
Full-Text Articles in Mechanical Engineering
Progressive Damage In Stitched Composites Under Impact Loading, Kwek Tze Tan, N. Watanabe, A. Yoshimura, Y. Iwahori, T. Ishikawa
Progressive Damage In Stitched Composites Under Impact Loading, Kwek Tze Tan, N. Watanabe, A. Yoshimura, Y. Iwahori, T. Ishikawa
Mechanical Engineering Faculty Research
Damage in carbon fibre reinforced plastics (CFRP) due to impact loading is an extremely complex phenomenon that comprises of multiple failure mechanisms like intra-laminar matrix cracks, interlaminar delamination, fibre pull-out and fibre fracture. In stitched composites, impact damage behavior is further complicated by the presence of through-thickness stitching [1, 2], which not only favorably increases mode I/II interlaminar strength [3, 4], but also inevitably creates geometrical defects like weak resin-rich pockets around stitch threads and misalignment of in-plane fibres. Computational modeling has been used to simulate progressive damage effectively [5]. However, the complexity of impact damage progression in stitched composites …
Long Term Outdoor Testing Of Low Concentration Solar Modules, Lewis Fraas, James Avery, Leonid Minkin, H. X. Huang, Tim Hebrink, Robert F. Boehm
Long Term Outdoor Testing Of Low Concentration Solar Modules, Lewis Fraas, James Avery, Leonid Minkin, H. X. Huang, Tim Hebrink, Robert F. Boehm
Mechanical Engineering Faculty Research
A 1‐axis carousel tracker equipped with four 3‐sun low‐concentration mirror modules has now been under test outdoors at the University of Nevada in Las Vegas (UNLV) for three years. There are three unique features associated with this unit. First, simple linear mirrors are used to reduce the amount of expensive single crystal silicon in order to potentially lower the module cost while potentially maintaining cell efficiencies over 20% and high module efficiency. Simple linear mirrors also allow the use of a single axis tracker. Second, the azimuth carousel tracker is also unique allowing trackers to be used on commercial building …
Enabling And Understanding Failure Of Engineering Structures Using The Technique Of Cohesive Elements, H. Jiang, Xiaosheng Gao, T. S. Srivatsan
Enabling And Understanding Failure Of Engineering Structures Using The Technique Of Cohesive Elements, H. Jiang, Xiaosheng Gao, T. S. Srivatsan
Mechanical Engineering Faculty Research
In this paper, we describe a cohesive zone model for the prediction of failure of engineering solids and/or structures. A damage evolution law is incorporated into a three-dimensional, exponential cohesive law to account for material degradation under the influence of cyclic loading. This cohesive zone model is implemented in the finite element software ABAQUS through a user defined subroutine. The irreversibility of the cohesive zone model is first verified and subsequently applied for studying cyclic crack growth in specimens experiencing different modes of fracture and/or failure. The crack growth behavior to include both crack initiation and crack propagation becomes a …
Influence Of Stitch Density And Stitch Thread Thickness On Compression After Impact Strength Of Stitched Composites, Kwek Tze Tan, N. Watanabe, Y. Iwahori, T. Ishikawa
Influence Of Stitch Density And Stitch Thread Thickness On Compression After Impact Strength Of Stitched Composites, Kwek Tze Tan, N. Watanabe, Y. Iwahori, T. Ishikawa
Mechanical Engineering Faculty Research
This study aims to investigate the influence of stitch density and stitch thread thickness on compression after impact (CAI) strength of stitched composites. Unstitched laminated composites and specimens stitched with varying stitch density and stitch thread thickness are subjected to impact damage and then compressive loading. It is shown that stitched composites have higher CAI strength than unstitched counterpart due to smaller impact-induced delamination area, where local buckling occurs during compressive failure. However, it is revealed that the effectiveness of stitching in suppressing delamination growth and inhibiting sublaminate buckling under compressive loading is intimately related to stitch density. It is …
Atomic Friction Studied By Modeling The Buried Inteface, Yalin Dong, Ashlie Martini, Qunyang Li, Robert W. Carpick
Atomic Friction Studied By Modeling The Buried Inteface, Yalin Dong, Ashlie Martini, Qunyang Li, Robert W. Carpick
Mechanical Engineering Faculty Research
Molecular dynamics simulation is carried out to model the single-asperity friction in atomic force microscope experiments. Superlubricity is achieved through misalignment between the AFM tip and substrate. Direct observation of the buried interface reveals that incommensurability-induced inhomogeneous shear stress can cause ultra-low atomic scale friction.
A New Look At Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung
A New Look At Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung
Mechanical Engineering Faculty Research
This paper deals with a controversial problem in answering the question “Does the optimum fin design always exist? If not, what are the optimization ranges and limitations?” These authors employ a general example of convecting-radiating trapezoidal annular fin with heat transfer at the tip and wall resistance at the interface. The present results indicate that the answer to the above first question is negative. The ranges of fin optimum design under different thermal and physical conditions are proposed. The effects of Biot number, radiation number, the heat loss at the tip, fin profile and overall wall resistance on fin optimization …
Diffuse-Charge Dynamics Of Ionic Liquids In Electrochemical Systems, Hui Zhao
Diffuse-Charge Dynamics Of Ionic Liquids In Electrochemical Systems, Hui Zhao
Mechanical Engineering Faculty Research
We employ a continuum theory of solvent-free ionic liquids accounting for both short-range electrostatic correlations and steric effects (finite ion size) [Bazant et al., Phys. Rev. Lett. 106, 046102 (2011)] to study the response of a model microelectrochemical cell to a step voltage. The model problem consists of a 1-1 symmetric ionic liquid between two parallel blocking electrodes, neglecting any transverse transport phenomena. Matched asymptotic expansions in the limit of thin double layers are applied to analyze the resulting one-dimensional equations and study the overall charge-time relation in the weakly nonlinear regime. One important conclusion is that our …
Role Of Hydrodynamic Behavior Of Dna Molecules In Dielectrophoretic Polarization Under The Action Of An Electric Field, Hui Zhao
Mechanical Engineering Faculty Research
A continuum model is developed to predict the dielectrophoretic polarizability of coiled DNA molecules under the action of an alternating current electric field. The model approximates the coiled DNA molecule as a charged porous spherical particle. The model explains the discrepancies among scaling laws of polarizability of different-sized DNA molecules with contour length and such discrepancies are attributed to different hydrodynamic behavior. With zero or one fitting parameter, theoretical predictions are in good agreement with various experimental data, even though in experiments there are some uncertainties in regard to certain parameters.
Streaming Potential Generated By A Pressure-Driven Flow Over Superhydrophobic Stripes, Hui Zhao
Streaming Potential Generated By A Pressure-Driven Flow Over Superhydrophobic Stripes, Hui Zhao
Mechanical Engineering Faculty Research
The streaming potential generated by a pressure-driven flow over a weakly charged slip-stick surface [the zeta potential of the surface is smaller than the thermal potential (25 mV)] with an arbitrary double layer thickness is theoretically studied by solving the Debye–Huckel equation and Stokes equation. A series solution of the streaming potential is derived. Approximate expressions for the streaming potential in the limits of thin double layers and thick double layers are also given in excellent agreement with the full solution. To understand the impact of the slip, the streaming potential is compared against that over a homogeneously charged smooth …