Dislocation Substructures Of Interstitial-Free Steel Subjected To Low Cycle Fatigue At Various Strain Amplitude,
2011
Department of Mechanical Engineering, R.O.C. Military Academy, Kaohsiung County, Taiwan, R.O.C.
Dislocation Substructures Of Interstitial-Free Steel Subjected To Low Cycle Fatigue At Various Strain Amplitude, Shih-Wei Mao, Wen-Chun Lo, Hsing-Lu Huang, New-Jin Ho
Journal of Marine Science and Technology–Taiwan
The aim of this wok is to study the fatigue properties in relation to the microstructures of interstitial-free (IF) steel, a representative of body center cubic (BCC) materials, subjected to low cycle periodic stress. In order to compare the grain size effect on dislocation development, we used samples of two distinctive grain sizes, 70 µm and 210 µm, prepared by different thermo-mechanical processes. We found (1) there was an initial softening when the stain amplitude was lower than 1.6% and the microstructure of the fatigued samples are cellular independent of the grain sizes and the amplitude of strain. (2) A …
Deformation Of Rolling Shutters Under Uniform Wind Pressure,
2011
Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
Deformation Of Rolling Shutters Under Uniform Wind Pressure, Nan-Nong Huang, San-Ming Chang
Journal of Marine Science and Technology–Taiwan
In this study, a model is developed to analyze the structural behaviors of rolling shutters subjected to wind pressure. In the current shutter theory, the elastic properties of shutters are characterized by two bending rigidities, which can be determined from the flexural tests of slats and shutters. Close form solutions can be obtained for the deflection of shutters with two opposite simply supported edges. To assess the validity of the present theory, rolling shutters with various sizes and supporting conditions under various magnitudes of loadings are tested. It is noted that the deflections and axial displacements based on the current …
Aerodynamic Performance And Shedding Characteristics On A Swept-Back Wing,
2011
Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
Aerodynamic Performance And Shedding Characteristics On A Swept-Back Wing, Shun-Chang Yen
Journal of Marine Science and Technology–Taiwan
A NACA 0012 finite swept-back wing with a sweep-back angle of 15° was utilized to investigate the effects of angle of attack (α) and the chord Reynolds number (Rec) on the vortex shedding and aerodynamic coefficients. A hot-wire anemometer was applied to measure the vortex-shedding frequency. The projected Strouhal number (Std) at various angles of attack was determined and discussed. The relationship between Std and α is regressed as: Std = -0.0008 α + 0.209, for 22° < α < 90°. Four characteristic surface-flow patterns: separation bubble, leading-edge bubble, bubble burst, and turbulent separation were classified by changing α and Re. The behavior of surface-flow structures significantly affects the lift, drag, and moment coefficients. The lift coefficient (CL) increases with α in the separation bubble and leading-edge bubble regimes. The maximum increase rate of CL with respect to α (d(CL)/dα) is 1.52 π/rad. Occurring in the leadingedge bubble regime. However, the maximum increase rate of drag coefficient (CD) with respect to α (d(CD)/dα) is 0.49 π/rad. Occurring in the bubble-burst regime. The steep-drop of moment coefficient at stall in the unswept-wings is not observed in the swept-back wings.
Hydrogen Absorption/Desorption In A Metal Hydride Reactor Accounting For Varied Effective Thermal Conductivity,
2011
Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung, Taiwan, R.O.C.
Hydrogen Absorption/Desorption In A Metal Hydride Reactor Accounting For Varied Effective Thermal Conductivity, Chih-Yuan Wang, Hwa-Chong Tien, San-Der Chyou, Nang-Nong Huang, Shing-Hoa Wang
Journal of Marine Science and Technology–Taiwan
This paper investigates the effect of varied effective thermal conductivity on the hydrogen absorption/desorption in a metal hydride (MH) reactor. The effective thermal conductivity of a metal hydride bed was measured by performing steady-state experiment and then compared with the results obtained by employing an existing model. Good agreement was found. Next, numerical simulation on the performance of hydrogen absorption/desorption of the MH reactor was conducted by assuming either varied or constant effective thermal conductivity. Corresponding hydrogen absorption/desorption experiment was performed for comparison. It was found that numerical simulation accounting for varied effective thermal conductivity agrees with the experimental data …
Mechatronics Application To Solar Tracking,
2011
Purdue University
Mechatronics Application To Solar Tracking, Danny L. Rodriguez Jr
Purdue Polytechnic Directed Projects
The purpose of this was to design and implement a two-axis solar tracking system utilizing the National Instruments C-Rio real time controller. In order to accomplish this a prototype was modeled in CAD. This prototype used two 12 V DC motors to change a solar panel's rotation and tilt based on feedback data from three cadmium sulfide photoresistors. This configuration was chosen for its ability to create both a left-right rotational and an up/down tilt differential. In Addition this approach uses National Instruments Labview to control a solar tracking system. Using Labview add uniqueness to this project by adding a …
Partnership For International Research And Education In Microfluidic Technology With Applications In Point Of Care Diagnostic,
2011
Department of Mechanical, Industrial and Systems Engineering, University of Rhode Island
Partnership For International Research And Education In Microfluidic Technology With Applications In Point Of Care Diagnostic, Mohammed Faghri, Sigrid Berka, John Grandin, Thomas Mather, D.M.L Meyer, Zongqin Zhang, Otto Gregory, Stephan Grilli, Christopher Baxter, Constantine Anagnostopoulos, Assem Abolmaaty
Discovery@URI
This poster summarizes the research highlights of a project conducted as part of an National Science Foundation (NSF) partnership for research and education. The objective of this multidisciplinary, international project was to conduct research on microfluidic technology and applications. The project team is comprised of participants from the University of Rhode Island and the Technical University of Braunschweig in Germany. The research focuses on the following four tasks: Task 1 – Discovery of disease biomarkers; Task 2 –Streaming based microfluidic platform for pumping, mixing, separation and detection; Task 3 – Development of rapid, quantitative and sensitive microfluidic fluorescence immunosensors for …
Development Of High Resolution Sea Floor Mapping Tools And Techniques,
2011
University of Rhode Island
Development Of High Resolution Sea Floor Mapping Tools And Techniques, Gabrielle Inglis, J. Ian Vaughn, Clara Smart, Christopher N. Roman
Graduate School of Oceanography Faculty Publications
There is a persistent need for high resolution photographic and bathymetric maps of the sea floor for many research areas in marine geology, biology and archaeology. This poster will present recent work using high frequency multibeam sonars, stereo vision and structured light laser imaging techniques to create maps with centimeter resolution for these applications. This research involves the development of new image and sonar processing techniques that combat the typical difficulties of imperfect navigation information, limited sensor ranges and adverse environmental conditions associated with using marine robotic vehicles in the ocean. Data for this work has been collected with the …
Effect Of Gold Content On The Reliability Of Snagcu Solder Joints,
2011
California Polytechnic State University - San Luis Obispo
Effect Of Gold Content On The Reliability Of Snagcu Solder Joints, Jianbiao Pan, Julie Silk, Mike Powers, Patrick Hyland
Industrial and Manufacturing Engineering
Electroplated Ni/Au over Cu is a popular metallization for PCB finish as well as for component leads, especially wire-bondable high frequency packages, where the gold thickness requirement for wirebonding is high. The general understanding is that less than 3 wt% of Au is acceptable in SnPb solder joints. However, little is known about the effect of Au content on the reliability of SnAgCu solder joints. The purpose of this study is to determine the acceptable level of Au in SAC305 solder joints. Three different package platforms with different Au thicknesses were assembled on boards with two different Au thicknesses using …
Evaluation Of Transient Refrigerant Migration Modeling Approach On Automotive Air Conditioning Systems,
2011
University of Illinois at Urbana-Champaign
Evaluation Of Transient Refrigerant Migration Modeling Approach On Automotive Air Conditioning Systems, Bin Li, Steffen Peuker, Pega Hrnjak, Andrew Alleyne
Mechanical Engineering
Automotive air conditioning systems are subject to constantly changing operation conditions and steady state simulations are not sufficient to describe the actual performance. The refrigerant mass migration during transient events such as clutch-cycling or start-up bas a direct impact on the transient performance. It is therefore necessary to develop simulation tools which can accurately predict the migration of the rerrigerant mass. To this end a dynamic model of an automotive air conditioning system is presented in this paper using a switched modeling framework. Model validation against experimental results demonstrates that the developed modeling approach is able to describe the transient …
Evaluating Impact Attenuator Performance For A Formula Sae Vehicle,
2011
Kettering University
Evaluating Impact Attenuator Performance For A Formula Sae Vehicle, Jason Fahland, Craig Hoff, Janet Brelin-Fornari
Mechanical Engineering Publications
Formula SAE® is one of several student design competitions organized by SAE International. In the Formula SAE events undergraduate and graduate students are required to conceive, design, fabricate and compete with a small, formula-style, race car. Formula SAE safety rules dictate a 7 m/s (or approximately 15.65 mph) frontal crash test for nose mounted impact attenuators. These rules are outlined in section B3.21 of the Formula SAE rule book. Development and testing methods of these energy absorbing devices have varied widely among teams. This paper uses real world crash sled results to research methods for predicting the performance of aluminum …
An Analysis Of Analytical Methods To Produce A Varying Angular Output From A Constant Angular Input Using Gearsets,
2011
Brigham Young University - Provo
An Analysis Of Analytical Methods To Produce A Varying Angular Output From A Constant Angular Input Using Gearsets, Isaac R. Jones
Theses and Dissertations
Research in developing a Positively Engaged Continuously Variable Transmission (PECVT) has been underway at Brigham Young University for some time. The inherent problems associated with embodiments of this type of transmission, namely the Non-Integer Tooth Problem (NITP), have been identified. This research is focused on the development of a Positively Engaged Piecewise Continuous Transmission (PEPCT), which is a subset of the PECVT. This document describes the hypothesis and analysis of using non-circular gearsets to overcome the NITP. This proposed solution enables a varying angular output from a constant angular input. In this research two analytical methods were evaluated based on …
Arra Advanced Weatherization Training Center - Quarterly Report (January 2011-March 2011),
2011
Florida Solar Energy Center
Arra Advanced Weatherization Training Center - Quarterly Report (January 2011-March 2011), Florida Solar Energy Center, Neil Moyer
FSEC Energy Research Center®
The 1st quarter of 2011 was the beginning of procurement for the training center. Two pieces of equipment, the insulation blowing machine and infrared cameras, were put out for quotes. Both have been selected and purchase orders created.
Strain Monitoring Of Carbon Fiber Composite With Embedded Nickel Nano-Composite Strain Gage,
2011
Brigham Young University - Provo
Strain Monitoring Of Carbon Fiber Composite With Embedded Nickel Nano-Composite Strain Gage, Timothy Michael Johnson
Theses and Dissertations
Carbon fiber reinforced plastic (CFRP) composites have extensive value in the aerospace, defense, sporting goods, and high performance automobile industries. These composites have huge benefits including high strength to weight ratios and the ability to tailor their properties. A significant issue with carbon fiber composites is the potential for catastrophic fatigue failure. To better understand this fatigue, there is first a huge push to measure strain accurately and in-situ to monitor carbon fiber composites. In this paper, piezoresistive nickel nanostrand (NiNs) nanocomposites were embedded in between layers of carbon fiber composite for real time, in situ strain monitoring. Several different …
Gas Embolic Factors In Cardiovascular Health,
2011
University of Nebraska-Lincoln
Gas Embolic Factors In Cardiovascular Health, Eric L. Cutler
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Gas emboli are a clinical issue often encountered in the space exploration, marine construction, and medical fields. Individuals involved with these disciplines will often have asympomatic gas emboli circulating throughout their bodies on a regular basis. A study into the impact of chronic asymptomatic gas emboli on the risk of atherosclerosis in humans is thus presented. This research utilized a custom built cardiovascular flow simulator and accompanying data acquisition system to experimentally determine the influence of gas emboli under varied circumstances on the mean wall shear stress of a tube in-vitro. A directly inverse relationship between gas embolus presence in …
Direct Numerical Simulation Of Hypersonic Turbulent Boundary Layers. Part 3. Effect Of Mach Number,
2011
Missouri Unviersity of Science and Technology
Direct Numerical Simulation Of Hypersonic Turbulent Boundary Layers. Part 3. Effect Of Mach Number, L. (Lian) Duan, I. Beekman, M. P. Martín
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In this paper, we perform direct numerical simulations (DNS) of turbulent boundary layers with nominal free-stream Mach number ranging from 0.3 to 12. The main objective is to assess the scaling's with respect to the mean and turbulence behaviors as well as the possible breakdown of the weak compressibility hypothesis for turbulent boundary layers at high Mach numbers (M > 5). We find that many of the scaling relations, such as the van Driest transformation for mean velocity, Walz's relation, Morkovin's scaling and the strong Reynolds analogy, which are derived based on the weak compressibility hypothesis, remain valid for the range …
The Composition And Distribution Of Coal-Ash Deposits Under Reducing And Oxidizing Conditions From A Suite Of Eight Coals,
2011
Brigham Young University - Provo
The Composition And Distribution Of Coal-Ash Deposits Under Reducing And Oxidizing Conditions From A Suite Of Eight Coals, David R. Brunner
Theses and Dissertations
Eighteen elements, including: carbon, oxygen, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, potassium, calcium, titanium, chromium, manganese, iron, nickel, strontium, and barium were measured using a scanning electron microscope with energy dispersive spectroscopy from deposits. The deposits were collected by burning eight different coals in a 160 kWth, staged, down-fired, swirl-stabilized combustor. Both up-stream and down-stream deposits from an oxidizing region (equivalence ratio 0.86) and reducing region (equivalence ratio 1.15) were collected. Within the deposits, the particle size and morphology were studied. The average particle cross-sectional area from the up-stream deposits ranged from 10 - 75 µm2 and had a …
Surface Geometry And Heat Flux Effect On Thin Wire Nucleate Pool Boiling Of Subcooled Water In Mictrogravity,
2011
Utah State University
Surface Geometry And Heat Flux Effect On Thin Wire Nucleate Pool Boiling Of Subcooled Water In Mictrogravity, Troy Munro, Heng Ban
Presentations
No abstract provided.
Multi-Resolution Obstacle Mapping With Rapidly-Exploring Random Tree Path Planning For Unmanned Air Vehicles,
2011
Brigham Young University - Provo
Multi-Resolution Obstacle Mapping With Rapidly-Exploring Random Tree Path Planning For Unmanned Air Vehicles, Brett Wayne Millar
Theses and Dissertations
Unmanned air vehicles (UAVs) have become an important area of research. UAVs are used in many environments which may have previously unknown obstacles or sources of danger. This research addresses the problem of obstacle mapping and path planning while the UAV is in flight. Online obstacle mapping is achieved through the use of a multi-resolution map. As sensor information is received, a quadtree is built up to hold the information based upon the uncertainty associated with the measurement. Once a quadtree map of obstacles is built up, we desire online path re-planning to occur as quickly as possible. We introduce …
Thermal Conductivity Of Interfacial Layers In Nanofluids,
2011
Missouri University of Science and Technology
Thermal Conductivity Of Interfacial Layers In Nanofluids, Zhi Liang, Hai-Lung Tsai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Thermal Conductivity of Interfacial Layers is an Essential Parameter for Determining How the Ordered Liquid Layering Around the Particle-Liquid Interface Contributes to the Unusual High Thermal Conductivity of Nanofluids. However, So Far There is No Experimental Data Regarding This Parameter. using Nonequilibrium Molecular Dynamics Simulations of an Inhomogeneous Au-Ar System in Which the Solid-Liquid Interactions Are Assumed to Be Much Stronger Than the Liquid-Liquid Interactions, We Show Explicitly that the Thermal Conductivity of a 1-Nm-Thick Interfacial Layer is 1.6∼2.5 Times Higher Than that of the Base Fluid. the Simulation Results Are Incorporated into a Three-Level Clustering Model to Calculate the …
Long Term Outdoor Testing Of Low Concentration Solar Modules,
2011
JX Crystals Inc.
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 …
