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Articles 31 - 60 of 133

Full-Text Articles in Mechanical Engineering

Collapse Resistance Of Moment Resisting Frame And Shear Wall Rc Structural Systems Exposed To Blast, Alaa I. Chehab, Christopher D. Eamon, Joshua Griffin Oct 2016

Collapse Resistance Of Moment Resisting Frame And Shear Wall Rc Structural Systems Exposed To Blast, Alaa I. Chehab, Christopher D. Eamon, Joshua Griffin

Civil and Environmental Engineering Faculty Research Publications

Various characteristics of a structure influence its response when subjected to a blast load. This has important implications for survivability and resistance to progressive collapse. In this study, the effect of the type of lateral load resisting system on reinforced concrete building resistance to progressive collapse when exposed to blast load is examined. Fourteen different reinforced concrete structures were considered for analysis, with five structures designed as moment resisting frames and nine designed as shear walls systems. Buildings with 3, 6, and 10 stories with 3, 4, and 5-bay symmetric configurations were considered. The structures were exposed to external and …


Evaluation Of Alternative Implementation Methods Of Failure Sampling Approach For Structural Reliability Analysis, Kapil Patki, Christopher D. Eamon Apr 2016

Evaluation Of Alternative Implementation Methods Of Failure Sampling Approach For Structural Reliability Analysis, Kapil Patki, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

In this paper, several alternative approaches are used to implement the failure sampling method for structural reliability analysis and are evaluated for effectiveness. Although no theoretical limitation exists as to the types of problems that failure sampling can solve, the method is most competitive for problems that cannot be accurately solved with reliability index-based approaches and for which simulation is needed. These problems tend to have non-smooth limit state boundaries or are otherwise highly nonlinear. Results from numerical integration and three extrapolation approaches using the generalized lambda distribution, Johnson's distribution, and generalized extreme value distribution are compared. A variety of …


Design Live Load Factor Calibration For Michigan Highway Bridges, Christopher D. Eamon, Valid Kamjoo, Kazuhiko Shinki Feb 2016

Design Live Load Factor Calibration For Michigan Highway Bridges, Christopher D. Eamon, Valid Kamjoo, Kazuhiko Shinki

Civil and Environmental Engineering Faculty Research Publications

In this study, a reliability-based calibration of live load factors for bridge design specific to the State of Michigan was conducted. Two years of high frequency WIM data from 20 representative state-wide sites were analyzed, and load effects were generated for bridge spans from 6 to 122 m (20 to 400 ft), considering simple and continuous moments and shears, as well as single lane and two lane effects. Seventy-five year statistics for maximum live load were then estimated with probabilistic projection. Bridge girders considered for the calibration included composite steel, prestressed concrete, side-by-side and spread box beams, as well as …


Field Tests Of Two Prestressed Concrete Girder Bridges For Live Load Distribution And Moment Continuity, Christopher D. Eamon, Alaa Chehab, Gustavo Parra-Montesinos Jan 2016

Field Tests Of Two Prestressed Concrete Girder Bridges For Live Load Distribution And Moment Continuity, Christopher D. Eamon, Alaa Chehab, Gustavo Parra-Montesinos

Civil and Environmental Engineering Faculty Research Publications

Two similar bridges constructed with a live load continuous connection were tested for live load distribution and joint continuity. Girder distribution factors (GDFs) were compared to AASHTO equivalent values. For positive moments on all girders as for negative moments on interior girders, results using AASHTO equivalent GDFs were found to be generally conservative. However, for negative moments on exterior girders, test results exceeded AASHTO values, with 2-lane results significantly so. GDF results were verified with a FEA model, which produced similar behavior to the field tests. With respect to joint continuity, it is estimated that a simple span would produce …


Combustion, Ionization And Sporadic Pre-Ignition In A Turbocharged Gasoline Direct Injection Engine., Shenouda Mekhael Jan 2016

Combustion, Ionization And Sporadic Pre-Ignition In A Turbocharged Gasoline Direct Injection Engine., Shenouda Mekhael

Wayne State University Dissertations

This research is focused on the use of ionization of combustion products in hydrocarbons-air flames to gain a better understanding of the combustion process in turbocharged gasoline direct injection engines. A GM 2.0 L Ecotec GDI-T engine is used in this investigation. The ion current is measured simultaneously by two in-cylinder combustion sensors: the spark plug and the fuel injector. The characteristics of the ion current signals produced by the two sensors are analyzed and correlated with the characteristics of the rate of heat release computed from the cylinder gas pressure. Since this is the first time for the fuel …


Design And Optimization Of Lithium Ion Battery For High Temperature Applications, Khalid Abdullitife Ababtain Jan 2016

Design And Optimization Of Lithium Ion Battery For High Temperature Applications, Khalid Abdullitife Ababtain

Wayne State University Dissertations

With massive commercial success of lithium ion batteries, the ability to operate at

and above 70 °C still a crucial issue and a safety concern to combat ever-increasing

global warming and to extend applications beyond portable electronics. Among various

components of battery, anode and electrolyte and the passivation layer formed between

them is crucial towards the development of Li-ion batteries for extendable temperature

range. In this regard, room temperature ionic liquids (RTILs) have the capability to

tackle thermal stability issues of lithium ion batteries but their poor compatibility with

traditional graphite anodes limits their practical application. Towards addressing this

issue, …


Development Of An Elderly Female Torso Finite Element Model For Restraint System Research And Development Applications, Anil Kalra Kalra Jan 2016

Development Of An Elderly Female Torso Finite Element Model For Restraint System Research And Development Applications, Anil Kalra Kalra

Wayne State University Dissertations

Elderly females are found to be one of the most vulnerable segments of population during motor vehicle crashes and their population is increasing in the coming decades. Current design of restraint systems as well as other passive safety measures are designed based on anthropomorphic details of younger population. Developing another dummy representing elderly female population is a costly effort, while a finite element (FE) model of elderly female with similar anthropomorphic details and age- and gender-specific material properties can be a better alternative solution. The current research focuses on the development of a FE model of an elderly female torso, …


Torque Accuracy Improvement Via Explicit Torque Feedback Control For Internal Combustion Spark Ignition Engines, Anwar Alkeilani Jan 2016

Torque Accuracy Improvement Via Explicit Torque Feedback Control For Internal Combustion Spark Ignition Engines, Anwar Alkeilani

Wayne State University Dissertations

At the present time, both control and estimation accuracies of engine torque are causes for under-achieving optimal drivability and performance in today’s production vehicles. The major focus in this area has been to enhance torque estimation and control accuracies using existing open-loop torque control and estimation structures. Such an approach does not guarantee optimum torque tracking accuracy and optimum estimation accuracy due to air flow and efficiencies estimations errors. Furthermore, current approach overlooks the fast torque path tracking which does not have any related feedback. Recently, explicit torque feedback control has been proposed in the literature using either estimated or …


An Experimental Investigation On The Effect Of Intake Charge Temperature And Injection Timing On Autoignition Of Low Cetane Number Fuel (Sasol Ipk), Swapnil Shekhar Bodele Jan 2016

An Experimental Investigation On The Effect Of Intake Charge Temperature And Injection Timing On Autoignition Of Low Cetane Number Fuel (Sasol Ipk), Swapnil Shekhar Bodele

Wayne State University Theses

ABSTRACT

AN EXPERIMENTAL INVESTIGATION ON THE EFFECT OF

INTAKE CHARGE TEMPERATURE AND INJECTION TIMING

ON AUTOIGNITION OF LOW CETANE NUMBER FUEL

(SASOL IPK)

by

SWAPNIL S BODELE

May 2016

Advisor: Dr. Naeim Henein

Major: Mechanical Engineering

Degree: Master of Science

Although diesel engines are considered the best powerhouses for their heavy-duty

capabilities, concerns have been raised because of their emission issues. Alternative

fuels like jet fuels can be substitute to them for improved efficiencies. The Department Of

Defense uses JP8 for their combat vehicles under their Single Fuel Concept for a better

logistic supply chain. However, due to the projected …


Experimental Strain Measurement In Ultrasonic Welding Of Battery Tabs, Chen Chen Jan 2016

Experimental Strain Measurement In Ultrasonic Welding Of Battery Tabs, Chen Chen

Wayne State University Theses

Lithium-ion battery is one the most popular types of batteries currently used in electric

vehicles. To meet the power requirement, hundreds of Lithium ion battery cells are connected together before being assembled into a battery pack. Ultrasonic welding is the most widely used joining technology to connect battery cells together. In an ultrasonic welding process, high frequency oscillation is used to generate small relative motions between sheet metals to be welded, and produce solid-state bonds between the sheet metals clamped under pressure. One of the major issues for battery pack ultrasonic welding is that sometimes the welding process damages the …


Electrocatalysis In Li-S Batteries, Hesham I. Al Salem Jan 2016

Electrocatalysis In Li-S Batteries, Hesham I. Al Salem

Wayne State University Dissertations

Stabilizing polysulfide-shuttle process while ensuring high sulfur loading holds the key to realize high theoretical energy density (2500 Wh/kg) of lithium-sulfur (Li-S) batteries. Though several carbon based porous materials have been used as host structures for sulfur and its intermediate polysulfides, the week adsorption of polysulfides on carbon surface and its poor reaction kinetics limits them from practical application. Here, we preset a novel ‘electcatalysis’ approach to stabilize polysulfide shuttle process and also enhance its red-ox kinetics. As a proof of concept, we have studied in-detail using conventional electrocatalyst i.e Pt/graphene composite, further the same extended to cost-effective electrocatalysts such …


Static And Dynamic Behavior Of Carbon Fiber Reinforced Aluminum (Carall) Laminates, Gurpinder Singh Dhaliwal Jan 2016

Static And Dynamic Behavior Of Carbon Fiber Reinforced Aluminum (Carall) Laminates, Gurpinder Singh Dhaliwal

Wayne State University Dissertations

STATIC AND DYNAMIC BEHAVIOUR OF CARBON FIBER REINFORCED ALUMINUM (CARALL) LAMINATES

by

GURPINDER SINGH DHALIWAL

Advisor: Dr. Golam Newaz

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The main aim of this research work was to investigate the static and dynamic properties of carbon fiber reinforced aluminum laminates cured without using any external adhesive and acid treatment of aluminum layers. A comprehensive study was undertaken to study the effect of adding epoxy resin rich polyester synthetic surface veil cloth layers on the failure modes and flexural and tensile response of these fiber metal laminates (FMLs). The main purpose of adding veil …


Arbitrary Lagrangian-Eulerian Method Investigation On Fuel Tank Strap Simulation Under Proving Ground Condition, Guangtian Song Jan 2016

Arbitrary Lagrangian-Eulerian Method Investigation On Fuel Tank Strap Simulation Under Proving Ground Condition, Guangtian Song

Wayne State University Dissertations

The Arbitrary Lagrangian-Eulerian (ALE) is a hybrid finite element formulation that can alleviate many of the drawbacks from the traditional Lagrangian-based and Eulerian-based finite element simulations, which is developed through combining modern algorithms for Lagrangian hydrodynamics, meshing technology and remap methods developed for high-resolution Eulerian methods. Lagrangian-based finite element formulations is that the computational system moves with the material and main drawback is that it will face severe problems to deal with strong distortions in the computational domain. Eulerian-based finite element formulations is that the computational system is a prior fixed in space and unable to deal easily with fluids …


Stop Identity Cues As A Cue To Language Identity, Paula Lisa Castonguay Jan 2016

Stop Identity Cues As A Cue To Language Identity, Paula Lisa Castonguay

Wayne State University Dissertations

The purpose of the present study was to determine whether language membership could potentially be cued by the acoustic-phonetic detail of word-initial stops and retained all the way through the process of lexical access to aid in language identification. Of particular interest were language-specific differences in CE and CF word-initial stops. Experiment 1 consisted of an interlingual homophone production task. The purpose of this study was to examine how word-initial stop consonants differ in terms of acoustic properties in Canadian English (CE) and Canadian French (CF) interlingual homophones. The analyses from the bilingual speakers in Experiment 1 indicate that bilinguals …


Rheology Of Cross-Linked Polymers And Polymer Foams: Theory And Experimental Results, John Herman Jan 2015

Rheology Of Cross-Linked Polymers And Polymer Foams: Theory And Experimental Results, John Herman

Wayne State University Dissertations

Typical polymers have a time-dependent response to loading which results in stress relaxation or creep. Models using springs/dashpots or Volterra integrals are capable of predicting the material response, but place little or no emphasis on the reasoning behind the response. This research proposes a microscopic reasoning behind polymer chain movement, while developing a model to predict the creep and stress relaxation of a polymer foam. Based on the theorized slip/stick of polymer chains as they slide past each other, this model successfully predicts the behavior of a PMI polymer foam under tensile loads. This model lends insights into polymer microscopic …


Specialized Inter-Particle Interaction Lbm For Patterned Superhydrophobic Surfaces, Amal Saeed Yagub Jan 2015

Specialized Inter-Particle Interaction Lbm For Patterned Superhydrophobic Surfaces, Amal Saeed Yagub

Wayne State University Dissertations

SPECIALIZED INTER-PARTICLE INTERACTION LBM FOR PATTERNED SUPERHYDROPHOBIC SURFACES

by

AMAL S. YAGUB

ABSTRACT:

Superhydrophobic surface characteristics are important in many industrial applications, ranging from the textile to the military. It was observed that surfaces fabricated with nano/micro roughness can manipulate the droplet contact angle, thus providing an opportunity to control the droplet wetting characteristics. The Shan and Chen (SC) lattice Boltzmann model (LBM) is a good numerical tool, which holds strong potentials to qualify for simulating droplets wettability. This is due to its realistic nature of droplet contact angle (CA) prediction on flat smooth surfaces. But SC-LBM was not able …


Face Sheet/Core Debonding In Sandwich Composites Under Static And Fatigue Loading, Manjinder Singh Warriach Jan 2015

Face Sheet/Core Debonding In Sandwich Composites Under Static And Fatigue Loading, Manjinder Singh Warriach

Wayne State University Dissertations

Delamination growth due to face sheet/core debonding is a major concern due to its inherent weakness in sandwich composites which can be exacerbated due to the presence of flaws. In this research work The primary objective of this research was to characterize the delamination crack growth behavior in E-glass face sheet/polyurethane foam core sandwich composite with pre-existing initial delamination crack at a face sheet/core interface under static and fatigue for mode I and mixed mode loading. For mode I static loading two types of delamination experiments, namely T-peel test and wedge test were implemented to evaluate fracture toughness in polyurethane …


Helmholtz Equation Least Squares Based Near-Field Acoustic Holography With Laser, Wu Zhu Jan 2015

Helmholtz Equation Least Squares Based Near-Field Acoustic Holography With Laser, Wu Zhu

Wayne State University Dissertations

This dissertation presents the HELS based NAH with laser and use normal surface velocity as input in near-field acoustic holography. The conventional HELS based NAH uses acoustic pressure as input to reconstruct sound field quantities, while this modified HELS based NAH with laser utilizes the normal surface velocities measured by LDV to reconstruct the acoustic quantities at interested positions. Theoretical principles of the HELS based NAH with laser have been fully developed and the method has been verified in theoretical perspective. Two theoretical examples verify that HELS based NAH with laser can obtain exactly the same results as analytic solution. …


Analysis And Suppression Of Engine Hood Vibrations Under Random Road Excitations, Hooman Farrokhzadeh Jan 2015

Analysis And Suppression Of Engine Hood Vibrations Under Random Road Excitations, Hooman Farrokhzadeh

Wayne State University Theses

Vehicle designs and developments must meet safety legislations along with market demands. Safety regulations are mainly concerned with how a vehicle body performs in crashes, during which pedestrian collision is the one of the most important issues. When a vehicle strikes a pedestrian, its engine hood will most likely hit the head of the pedestrian, causing serious injuries. To reduce the severity of the injuries, along with market demands to improve vehicle fuel economy and performance, engineers have considered the design solution of reduction of the vehicle hood thickness (and hence its weight) and the use of advanced light materials. …


Advancement And Validation Of A Plug-In Hybrid Electric Vehicle Model Utilizing Experimental Data From Vehicle Testing, Kevin Lloyd Snyder Jan 2015

Advancement And Validation Of A Plug-In Hybrid Electric Vehicle Model Utilizing Experimental Data From Vehicle Testing, Kevin Lloyd Snyder

Wayne State University Theses

The objective of the research into modeling and simulation was to provide an iterative improvement to the Wayne State EcoCAR 2 team's math-based design tools for use in evaluating different outcomes based on hybrid powertrain architecture tweaks, controls code development and testing. This thesis includes the results of the team's work in the EcoCAR 2 competition for university student teams to create and test a plug-in hybrid electric vehicle for reducing petroleum oil consumption, pollutant emissions, and Green House Gas (GHG) emissions.

Plant model validations and advancements brought the vehicle plant model directionally closer to the actual vehicle's experimental data …


Experimental Investigation On Combustion And Ionization During Cold Starting And Idling Of A Diesel Engine, Sahil Deodatta Sane Jan 2015

Experimental Investigation On Combustion And Ionization During Cold Starting And Idling Of A Diesel Engine, Sahil Deodatta Sane

Wayne State University Theses

Diesel engine performance during cold starting is very crucial for smooth engine start at undesirable emission level. The development of cold start strategies that improve combustion stability relies mainly on the understanding of the combustion process during the cold starting. Even for modern diesel engines, the conditions during the cold start is far from normal operation characterized by large amount of unburned hydrocarbon emissions and long start to idling time. Thus, the use of an in-cylinder combustion sensor to measure the combustion quality during engine starting can significantly improve engine cold start control strategies. The ion current sensor has the …


The Study Of Ionization In A Military, Heavy-Duty, Diesel Engine, Steven Zielinski Jan 2015

The Study Of Ionization In A Military, Heavy-Duty, Diesel Engine, Steven Zielinski

Wayne State University Theses

This thesis is an investigation of ionization in a military, heavy-duty, diesel engine. Ionization is a phenomenon which occurs in both spark-ignited and diesel engines. During the reactions of combustion, charged molecules and electrons are produced. The current produced, ion current, from these charges can be measured. The measurement of ion current can serve as an in-cylinder diagnostic for closed-loop engine control strategies. In this work, a literature review was performed to survey previous work as it pertains to ionization in diesel engines. In addition, a detailed description and comparison of the HEUI injection system was made to HPCR. This …


Effect Of Impact Damage On Compression-Compression Fatigue Behavior Of Sandwich Composites, Ali M. Al-Sharif Jan 2015

Effect Of Impact Damage On Compression-Compression Fatigue Behavior Of Sandwich Composites, Ali M. Al-Sharif

Wayne State University Dissertations

The aim of this research work was to investigate the effect of impact damage on in-plane buckling and compression-compression fatigue behavior for a new sandwich structure made from E-glass/epoxy face sheets over end-grain balsa wood core. Low velocity impact tests were carried out using a drop-weight impact tower by impacting the sandwich beam at the center with energy level slightly higher than threshold energy level of 8.8 J. Edge-wise compression static tests were conducted for impacted and non-impacted samples to address energy absorption characteristics of these composites. Analytical and experimental investigations were carried out to measure critical buckling loads and …


Quantification Of Auto-Ignition In Diesel Engines, Umashankar M. Joshi Jan 2015

Quantification Of Auto-Ignition In Diesel Engines, Umashankar M. Joshi

Wayne State University Dissertations

Efforts have been made previously by researchers to quantify the auto-ignition quality of fuels by calculating global activation energy using Arrhenius plots with data measured for the ignition delay period (ID). Large variation in the activation energy of fuels has been observed even for fuels with closer CN values. More recently, the activation energy values obtained by Kook et al in (2005) on an optical engine do not agree with data obtained in an identical metallic engine by Jayakumar using fuels of same CN.

The disparity in their results can be attributed to the differences in ignition delay (ID) and …


Methodology For Validating Multi-Dimensional Engine Combustion Models And Fuel Surrogates Using An Optically Accessible Compression Ignition Engine, Xin Yu Jan 2015

Methodology For Validating Multi-Dimensional Engine Combustion Models And Fuel Surrogates Using An Optically Accessible Compression Ignition Engine, Xin Yu

Wayne State University Dissertations

In response to increasingly stringent engine emissions regulation, three dimensional in-cylinder combustion modeling is increasingly being used as a tool to optimize the combustion process and reduce the cost of experimental testing. Due to the complexity of the physical and chemical interactions involved in the in-cylinder combustion process, the engine combustion model consists of numerous sub-models developed under pre-defined initial and boundary conditions requiring further model calibration depending on different engine applications. Fuel surrogates, one of those sub-models developed for different combustion applications, may not capture all the behavior when applied to the varying temperature-pressure conditions present in a compression …


Edge Fracture Prediction Of Dual Phase Steels With Consideration Of Microstructures, Ming Wen Jan 2015

Edge Fracture Prediction Of Dual Phase Steels With Consideration Of Microstructures, Ming Wen

Wayne State University Dissertations

In recent years, Advanced High Strength Steels (AHSS) have been used for the lightweight structural design and manufacturing in automotive industry. This class of sheet metals are prone to edge fracture during stamping production, and the fracture often occurs at much lower strain than that predicted based on the forming limit curves. The uncertainty in predicting edge fracture represents a great challenge in the application of AHSS. This dissertation is focused on the better understanding of edge fracture phenomenon through experimental observation and computer modeling with the consideration of microstructure effect.

In this dissertation, Hole Expansion (HE) test was used …


Assortment Planning Of Automotive Products: Considerations For Economic And Environmental Impacts Of Technology Selection, Ali Taghavi, Ratna Babu Chinnam May 2014

Assortment Planning Of Automotive Products: Considerations For Economic And Environmental Impacts Of Technology Selection, Ali Taghavi, Ratna Babu Chinnam

Industrial and Systems Engineering Faculty Research Publications

A manufacturer’s assortment is the set of products that the company offers to its customers. Assortment planning considerably affects both the sales revenue and product offering costs for the company and it had experienced growing attention across different industries over recent decades. In this study, we propose a modeling framework that seeks to identify the optimal assortment for a manufacturer of configurable products (in particular, automobiles). Our model accounts for environmental considerations (Corporate Average Fuel Economy requirements, tail-pipe emissions, and greenhouse gas emissions related to the production of the fuel used to power the vehicle) during assortment planning. We formulate …


Pedestrian Head Protection During Car To Pedestrian Accidents: In The Event Of Primary Impact With Vehicle And Secondary Impact With Ground, Vishal Gupta Jan 2014

Pedestrian Head Protection During Car To Pedestrian Accidents: In The Event Of Primary Impact With Vehicle And Secondary Impact With Ground, Vishal Gupta

Wayne State University Dissertations

Current regulations for assessing pedestrian safety use a simplified test setup that ignores many real-world factors. In particular, the level of protection is assessed using a free-motion headform impacting the vehicle's hood at a fixed angle. As such, this test setup does not capture the effect due to the vehicle front-end profile, nor does it comprehend injury due to a possible secondary impact of the pedestrian's head with ground. This thesis aims to numerically simulate vehicle to pedestrian crashes to develop knowledge that may suggest ways to improve safety above and beyond the regulatory tests. Inputs to the simulations include …


Analysis Of A Dual Scissored-Pair,Variable-Speed, Control Moment Gyroscope Driven Spherical Robot, Richard Chase Jan 2014

Analysis Of A Dual Scissored-Pair,Variable-Speed, Control Moment Gyroscope Driven Spherical Robot, Richard Chase

Wayne State University Dissertations

The objective of this research is to compare barycenter offset based designs of spherical robots to control moment gyroscope (CMG) based designs in order to determine which approach is most effective. The first objective was to develop a list of current state of the art designs in order to gain an overall understanding of what the obstacles in this area of research were. The investigation showed that barycenter offset designs can produce a low, continuous output torque, whereas CMG based designs can usually only produce a high, momentary output torque. The second objective was to develop a CMG based design …


Visualizing Interior And Exterior Jet Aircraft Noise, Manmohan Singh Moondra Jan 2014

Visualizing Interior And Exterior Jet Aircraft Noise, Manmohan Singh Moondra

Wayne State University Dissertations

In today's competitive aerospace industry, the quest for quiet has drawn significant attention to both the interior and exterior design of an airplane. Understanding the noise generation mechanisms of a jet aircraft is a crucial first step toward developing the most cost-effective noise and vibrations abatement methods. In this investigation, the Helmholtz Equation Least Squares (HELS) based nearfield acoustic holography will be used to understand noise transmission caused by jet engine and turbulence into the fuselage of a jet aircraft cruising at 30,000 ft.

Modern propulsive jet engines produce exterior noise sources with a high amplitude noise field and complicated …