Open Access. Powered by Scholars. Published by Universities.®

Mechanical Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 15721 - 15750 of 30246

Full-Text Articles in Mechanical Engineering

A Model Analysis Of Sand Insertion In Hydraulic Fractures, Ya Hao Dec 2015

A Model Analysis Of Sand Insertion In Hydraulic Fractures, Ya Hao

Mechanical and Aerospace Engineering Theses - Archive

Hydraulic fracturing (fracking) is a well-stimulation technology to create large volume of fracture formation in rocks for gas and/or oil extraction. This technology has been applied to commercially exploit natural gas in unconventional shale reservoirs that contain immense quantity but low density of hydrocarbon sources. The productivity can be largely dependent on the connectivity of fractures that must stay open. However, upon initial hydraulic fracturing, the fractures would be closed due to high hydrostatic pressure deep inside the crust. Sand must be pumped into the fractures to keep them open. An in-depth understanding of the sand distribution and its dependence …

Go to article

Magnetic Field Enhanced Thermal Conductivity Analysis Of Magnetic Nanofluids, Christopher Allen Dec 2015

Magnetic Field Enhanced Thermal Conductivity Analysis Of Magnetic Nanofluids, Christopher Allen

Mechanical and Aerospace Engineering Theses - Archive

The magnetic properties of four water-based nanofluids consisting of Al2O3, CuO, Fe3O4, and SiO2 were exploited to analyze the effect of the application of an external magnetic field on the thermal conductivity of the nanofluid. When the magnetic field is applied, the magnetic dipole moments of the particles align and the particles come in contact with each other and form chains in the direction of the applied magnetic field. When parallel to the direction of heat flow, the magnetic field causes the effective thermal conductivity in the direction of the magnetic field to increase. A higher thermally conductive fluid can …

Go to article

Design For Reduction Of Noise Produced By Natural Gas Regulator, Britany L. Chamberlain Dec 2015

Design For Reduction Of Noise Produced By Natural Gas Regulator, Britany L. Chamberlain

Undergraduate Honors Capstone Projects

This document describes the design of a multi-stage restrictive orifice device (MSRO) that serves to reduce the noise produced by a regulator valve. The scope of this document explains the determination of the proper design through the development of analytical models, the design of a test fixture to obtain empirical data, and the corroboration of the models with empirical data to obtain a working solution.

Go to article

Machine Components Test, Brandon Younger, Lauren Romero, Carlos Padilla Dec 2015

Machine Components Test, Brandon Younger, Lauren Romero, Carlos Padilla

Mechanical Engineering

To enhance California Polytechnic State University’s Mechanical Engineering program, Dr. Schuster has sponsored Brandon Younger, Lauren Romero, and Carlos Padilla to design and develop a new lab for students in the Intermediate Design class to test real mechanical components. This report discusses the background and ideation process that lead to the development of the Educational Mechanical Breadboard for Transmission System Components (Machine Components Test). Additionally, detailed drawings, 3D modeling, testing plans, and analysis are included to show how the Machine Components Test design will work and be validated.

Go to article

Carbon Articulating Backpack Spine, Salvatore Monforte Iii, Darci Lawrence, Savan Patel Dec 2015

Carbon Articulating Backpack Spine, Salvatore Monforte Iii, Darci Lawrence, Savan Patel

Mechanical Engineering

In the field, firefighters and Urban Search and Rescue (USAR) personnel need to transport variable loads efficiently, safely, and comfortably while simultaneously performing certain physical tasks. Current models of external and internal framed backpacks distribute the load of a pack efficiently, but do not allow for the natural movement of the wearer. Wolfpack Gear, Inc. proposed the need for a system which both effectively carries a load and allows for the unhindered natural movement of the user. The goal of this project was to design, build, and test an articulating backpack support system. The first stage of the project comprised …

Go to article

Squirting Balloon Toy, Rachael Schelley, Elizabeth Wilhelm Dec 2015

Squirting Balloon Toy, Rachael Schelley, Elizabeth Wilhelm

Mechanical Engineering

The main goal of the Squirting Balloon Toy project was to create a new toy that combined both a helium balloon and a squirting water component near the base of the balloon. The toy will be sold at theme parks, fairs, and to other retailers such as toy stores with the target audience of primarily children and their parents, or any individuals seeking a good laugh when they spray their unsuspecting target. As a result, the toy was designed to be both visually appealing and to have an element of surprise. After testing and analyzing four different conceptual designs, two …

Go to article

Gaf Glass Mat Splice Table Improvements, Grant Haug, Kevin Lansang, Ronald Lam, Michael Mooney Dec 2015

Gaf Glass Mat Splice Table Improvements, Grant Haug, Kevin Lansang, Ronald Lam, Michael Mooney

Mechanical Engineering

The GAF asphalt shingle production line in Shafter, CA requires continuous operation in order to maximize production efficiency. The assembly line process begins with feeding a large roll of fiberglass web into an accumulator. However, once the fiberglass roll approaches the end, it must be spliced with a new roll in order to maintain continuous feed into the production line. The splicing process must be fast and reliable to prevent any delay of the production line. Currently, this process is performed by two workers who manually feed the new fiberglass roll, align the two mats, cut the mats, apply glue …

Go to article

Three Degree-Of-Freedom Parallel Actuator Telescope Mount, Garrett Daniel Gudgel Dec 2015

Three Degree-Of-Freedom Parallel Actuator Telescope Mount, Garrett Daniel Gudgel

Master's Theses

This thesis contains the design, implementation, and testing of an original, small-scaled two degree-of-freedom telescope mount and a medium-scaled three degree-of-freedom telescope mount inspired by the six degree-of-freedom Stewart-Gough platform telescope mount. The end product is intended to achieve research-standard resolution of targeted sky coverage for binary star research. The scaled prototype was carried through concept design, manufacturing, software development, and testing. The mount software development and electronic design is applicable to a full-scale mount as the drivers have been designed to be easily adapted to different actuator configurations. It is recommended that this design be implemented into a telescope …

Go to article

Process Development For Compression Molding Of Hybrid Continuous And Chopped Carbon Fiber Prepreg For Production Of Functionally Graded Composite Structures, Corinne Marie Warnock Dec 2015

Process Development For Compression Molding Of Hybrid Continuous And Chopped Carbon Fiber Prepreg For Production Of Functionally Graded Composite Structures, Corinne Marie Warnock

Master's Theses

Composite materials offer a high strength-to-weight ratio and directional load bearing capabilities. Compression molding of composite materials yields a superior surface finish and good dimensional stability between component lots with faster processing compared to traditional manufacturing methods. This experimental compression molding capability was developed for the ME composites lab using unidirectional carbon fiber prepreg composites. A direct comparison was drawn between autoclave and compression molding methods to validate compression molding as an alternative manufacturing method in that lab. A method of manufacturing chopped fiber from existing unidirectional prepreg materials was developed and evaluated using destructive testing methods. The results from …

Go to article

Could Application Of Column-Grid-Array (Cga) Technology Result In Inelastic-Strain-Free State-Of-Stress In Solder Material?, Ephraim Suhir, Reza Ghaffarian, Johann Nicolics Dec 2015

Could Application Of Column-Grid-Array (Cga) Technology Result In Inelastic-Strain-Free State-Of-Stress In Solder Material?, Ephraim Suhir, Reza Ghaffarian, Johann Nicolics

Mechanical and Materials Engineering Faculty Publications and Presentations

Physically meaningful and easy-to-use analytical stress model is developed for a short cylinder (beam) clamped at the ends and subjected to bending caused by the ends offset. The offset is due, in its turn, to an external lateral force that has to be determined from the known offset. It is envisioned that such a beam can adequately represent the state of stress in a column-grid-array (CGA) solder joint interconnection experiencing thermal loading due to the thermal expansion/contraction mismatch of the IC package and the printed circuit board (PCB). The CGA designs are characterized by considerably higher stand-off heights than ball-grid-array …

Go to article

Studying The Optimum Design Of Automotive Thermoelectric Air Conditioning, Alaa Attar Dec 2015

Studying The Optimum Design Of Automotive Thermoelectric Air Conditioning, Alaa Attar

Dissertations

The remarkable amount of research being conducted on thermoelectrics gives the impression that this technology will have a bright future in power generation and temperature control systems. At the present time, thermoelectrics is applied widely for temperature control, but has not yet replaced conventional air-conditioning systems due to its lower performance. Currently, approximately 10% of annual vehicle fuel consumption corresponds to the air-conditioning system used to cool the vehicle cabin. Conventional air-conditioning systems cool the entire cabin; however, about 73% of a vehicle’s mileage occurs while the driver is the only occupant. These facts indicate the need for a single …

Go to article

Design Of A Meta-Material With Targeted Nonlinear Deformation Response, Zachary Satterfield Dec 2015

Design Of A Meta-Material With Targeted Nonlinear Deformation Response, Zachary Satterfield

All Theses

The M1 Abrams tank contains track pads consist of a high density rubber. This rubber fails prematurely due to heat buildup caused by the hysteretic nature of elastomers. It is therefore desired to replace this elastomer by a meta-material that has equivalent nonlinear deformation characteristics without this primary failure mode. A meta-material is an artificial material in the form of a periodic structure that exhibits behavior that differs from its constitutive material. After a thorough literature review, topology optimization was found as the only method used to design meta-materials. Further investigation determined topology optimization as an infeasible method to design …

Go to article

Co-Design Of Dynamic Real-Time Scheduling And Cooperative Control For Human-Agent Collaboration Systems Based On Mutual Trust, Xiaotian Wang Dec 2015

Co-Design Of Dynamic Real-Time Scheduling And Cooperative Control For Human-Agent Collaboration Systems Based On Mutual Trust, Xiaotian Wang

All Theses

Mutual trust is a key factor in human-human collaboration. Inspired by this social interaction, we analyze human-agent mutual trust in the collaboration of one human and (semi)autonomous multi-agent systems. In the thesis, we derive time-series human-agent mutual trust models based on results from human factors engineering. To avoid both over- trust and under-trust, we set up dynamic timing models for the multi-agent scheduling problem and develop necessary and sufficient conditions to test the schedulability of the human multi-agent collaborative task. Furthermore, we extend the collaboration between one human and multiple agents into the collaboration between multi-human network and swarm-based agents …

Go to article

Experimental Investigation Of Heat Leakage And Air Leakage In Domestic Refrigerators, Shervin Shoai Naini Dec 2015

Experimental Investigation Of Heat Leakage And Air Leakage In Domestic Refrigerators, Shervin Shoai Naini

All Theses

The optimization of the energy consumption in household refrigerators should consider the influence of the gasket which determines the heat transfer and air infiltration rate. In this research project, engineering methods are developed to evaluate the heat leakage due to the gasket and air infiltration in domestic refrigerators. In the first study, experimental and numerical approaches are applied to evaluate the gasket heat transfer based on the “Reverse Heat Load Method”. The main objective is to find the effective heat leakage with the dimensions of energy leakage per gasket length per temperature difference (W/m.K). An insulated cubic box with a …

Go to article

Control Of Thermoforming Process Parameters To Manufacture Surfaces With Pin-Based Tooling, Vijay Sarthy Mysore Sreedhara Dec 2015

Control Of Thermoforming Process Parameters To Manufacture Surfaces With Pin-Based Tooling, Vijay Sarthy Mysore Sreedhara

All Theses

Many manufacturing processes used to mass produce parts rely on expensive and time consuming tooling. These processes include sheet metal forming, injection molding, casting, and thermoforming. The time invested in design and development of tooling can be justified for high-production volumes. However, for low-volume production and customized products, the tooling investment cannot be amortized. Flexible tooling has been developed to address the needs of smaller production volumes. Reconfigurable pin tooling is an example of flexible tooling that relies on a matrix of adjustable-height pins to produce approximate surfaces. A key challenge in pin-based tooling is achieving accurate high quality surfaces …

Go to article

Structural Optimization Using Parametric Programming Method, Krupakaran Ravichandraan Dec 2015

Structural Optimization Using Parametric Programming Method, Krupakaran Ravichandraan

All Theses

The Parametric Programming method is investigated to consider its applicability to structural optimization problems. It is used to solve optimization problems that have design variables as implicit functions of some independent input parameter(s). It provides optimal solutions as a parametric function of the input parameter(s) for the entire parameter space of interest. It does not require the detailed discrete optimizations needed at a large number of parameter values as in traditional non-parametric optimization. Parametric programming is widely used in optimal controls, model predictive control, scheduling, process synthesis and material design under uncertainty due to the above mentioned benefits. Its benefits …

Go to article

A Novel Approach To Evaluating Compact Finite Differences And Similar Tridiagonal Schemes On Gpu-Accelerated Clusters, Ashwin Trikuta Srinath Dec 2015

A Novel Approach To Evaluating Compact Finite Differences And Similar Tridiagonal Schemes On Gpu-Accelerated Clusters, Ashwin Trikuta Srinath

All Theses

Compact finite difference schemes are widely used in the direct numerical simulation of fluid flows for their ability to better resolve the small scales of turbulence. However, they can be expensive to evaluate and difficult to parallelize. In this work, we present an approach for the computation of compact finite differences and similar tridiagonal schemes on graphics processing units (GPUs). We present a variant of the cyclic reduction algorithm for solving the tridiagonal linear systems that arise in such numerical schemes. We study the impact of the matrix structure on the cyclic reduction algorithm and show that precomputing forward reduction …

Go to article

Analysis And Synthesis Of Effective Human-Robot Interaction At Varying Levels In Control Hierarchy, David Spencer Dec 2015

Analysis And Synthesis Of Effective Human-Robot Interaction At Varying Levels In Control Hierarchy, David Spencer

All Theses

Robot controller design is usually hierarchical with both high-level task and motion planning and low-level control law design. In the presented works, we investigate methods for low-level and high-level control designs to guarantee joint performance of human-robot interaction (HRI). In the first work, a low-level method using the switched linear quadratic regulator (SLQR), an optimal control policy based on a quadratic cost function, is used. By incorporating measures of robot performance and human workload, it can be determined when to utilize the human operator in a method that improves overall task performance while reducing operator workload. This method is demonstrated …

Go to article

A Study On Evaporative Cooling For Data Centers & Artificial Neural Network Modeling, Pritam Karmokar Dec 2015

A Study On Evaporative Cooling For Data Centers & Artificial Neural Network Modeling, Pritam Karmokar

Mechanical and Aerospace Engineering Theses - Archive

This study mainly aims at exploring how, one of the best “Green” solutions for IT equipment cooling aka Evaporative Cooling, can be optimized for better future deployment. Also, this study focuses on ways to deploy Artificial Neural Network models to Dynamic Systems. Today, SERVERS are one of most important devices that our technology driven world cannot do without. Efficiently cooling these delicate yet highly power dense beasts, while being environment friendly is one of our prime concerns. This study is a combination of two deceptively divergent works. First, on exploring the workings of this technique by investigating one such Evaporative …

Go to article

Cae Analysis On A Ford Ecoboost Mustang Connecting Rod For Forged Steel, Aluminum 7075, Shiva Prasad Keralapura Basavaraju Dec 2015

Cae Analysis On A Ford Ecoboost Mustang Connecting Rod For Forged Steel, Aluminum 7075, Shiva Prasad Keralapura Basavaraju

Mechanical and Aerospace Engineering Theses - Archive

Connecting rod is high volume production critical component in an automobile engine. Every Internal combustion engine uses a connecting rod. Connecting rod must have highest possible rigidity with lowest possible weight. The major stress developed in the connecting rod are axial stress, due to combustion chamber pressure, and bending stress, due to centrifugal effect. Connecting rod mainly fails due to fatigue; according to survey, about 90% of the time the failure is due to fatigue. CAE analysis on Ford Eco boost Mustang connecting rod is carried out to validate the life of the connecting rod for forged steel and Aluminium7075. …

Go to article

Computational Model For Steady State Simulation Of A Plate-Fin Heat Exchanger, Ajit Rajesh Desai Dec 2015

Computational Model For Steady State Simulation Of A Plate-Fin Heat Exchanger, Ajit Rajesh Desai

Mechanical and Aerospace Engineering Theses - Archive

High performance heat transfer devices are critical components in hybrid power generation systems. The design of a Recuperator for 'waste heat recovery' is crucial for reducing the operating cost of a hybrid system. Plate-fin heat exchangers occupy a special position among high performance heat exchangers because of the compactness, efficiency and flexibility they offer. The performance of these heat exchange devices is typically very sensitive to fluid property variations, axial conduction and heat losses to environment. This thesis presents a numerical model of a plate fin heat exchanger in which fluid property variations including temperature driven changes in specific heat …

Go to article

Final Project Report: Heliostat-Concentrator Solar Cooker, Ian Davison, Devin Mast Dec 2015

Final Project Report: Heliostat-Concentrator Solar Cooker, Ian Davison, Devin Mast

Mechanical Engineering

This document is the full report for the senior project of Cal Poly Mechanical Engineering students Ian Davison and Devin Mast. The report encompasses the full project process, including background research, identification of need, design requirements, design development, proposed design, design realization, changes to proposed design, and design verification. We were tasked with the design and manufacture of a “dual mirror” solar cooker to verify a concept for a new type of off-axis parabolic solar cooker conceived by Dr. Pete Schwartz, the sponsor of the senior project and a physics professor at Cal Poly. Previously, off-axis parabolic solar cookers have …

Go to article

Development Of A Set Of Force Response Equations To Represent The Musculature In Infants To Study Development Dysplasia Of The Hip, Brendan Jones Dec 2015

Development Of A Set Of Force Response Equations To Represent The Musculature In Infants To Study Development Dysplasia Of The Hip, Brendan Jones

HIM 1990-2015

This paper describes how a force response equation was created to model muscles, tendons, and ligaments of the hip joint to improve a biomechanical model of an infant hip to study Developmental Dysplasia of the Hip (DDH). DDH is the most common abnormality in newborn infants and is defined as any amount of instability in the hip including complete dislocation. Researchers at our institution are attempting to increase the success rate of treatment methods by creating computer models of the biomechanics of infant hip instability and dislocation. The computer model used a scaled adult pelvis, femur, tibia, fibula and foot …

Go to article

Design Of A Physical Windkessel Model For Use In Lvad In-Vitro Benchtop Modeling, Kyle W. Beggs Dec 2015

Design Of A Physical Windkessel Model For Use In Lvad In-Vitro Benchtop Modeling, Kyle W. Beggs

HIM 1990-2015

Despite improved life expectancy compared to medical management alone, Ventricular Assist Device (VAD) recipients show survival rates of 80% at 12 months and 70% at 24 months. A large portion of VAD-associated mortality results from increased risk of stroke with an event frequency reported between 14-47%. Recent concerns have been raised about unprecedented increases of thrombus formation in VAD recipients with subsequent reports pointing towards implantation techniques as a critical contributor to these events. Thus, the overall prognosis with mechanical support can improve by advancing the surgeon’s approach to VAD implantation. Previous studies using Computational Fluid Dynamics (CFD) were aimed …

Go to article

Effects Of Binary Solvent System On Morphology Of Particles, Patrick Besana Dec 2015

Effects Of Binary Solvent System On Morphology Of Particles, Patrick Besana

HIM 1990-2015

Recent advancements in cancer research has led to the synthesis of a new drug known as docetaxel. Meant to replace paclitaxel, its more natural counterpart whose ingredients are difficult to obtain, the drug is known to effectively treat a wide array of cancers, including breast cancer, ovarian cancer, and prostate cancer. The establishment of a synthetic alternative to paclitaxel has increased its bioavailability, thereby lowering the cost needed to utilize the drug. Still, the limiting factor in minimizing costs is the method in which the drug is processed. Current methods in drug processing have their limitations, which include the introduction …

Go to article

Comments On “The Principal Axes Decomposition Of Spatial Stiffness Matrices”, Shuguang Huang, Joseph M. Schimmels Dec 2015

Comments On “The Principal Axes Decomposition Of Spatial Stiffness Matrices”, Shuguang Huang, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

A significant amount of research has been directed toward developing a more intuitive appreciation of spatial elastic behavior. Results of these analyses have been described in terms of behavior decompositions and in terms of behavior centers. In a recent paper entitled “The Principal Axes Decomposition of Spatial Stiffness Matrices” by Chen et al. (IEEE Trans. Robot., vol. 31, no. 1, pp. 191-207), a decomposition of spatial stiffness was presented, and centers of stiffness and compliance were identified. The results presented in the paper have substantial overlap with previously published results and redefine previously used terms. The objective of this communication …

Go to article

Springback Force Considerations In Compliant Haptic Interfaces, Dallin R. Swiss Dec 2015

Springback Force Considerations In Compliant Haptic Interfaces, Dallin R. Swiss

Theses and Dissertations

This thesis investigates the potential benefits and challenges of using compliant mechanisms in the design of haptic interfaces. The benefits and challenges are presented with an emphasis on their inherent springback behavior and an active compensation approach. Design criteria for compliant mechanism joint candidates are reviewed and several joints are surveyed. Quantitative calculations of axial stiffness and maximum stress for five candidates are presented. Generalized analytical models of springback force and compensation torque are created to simulate the implementation of each joint candidate in a two degree-of-freedom planar pantograph. We use these models in the development and discussion of an …

Go to article

Elucidating The Mechanisms Of Rate-Dependent Deformation At Ambient Temperatures In A Model Metallic Glass, Matthew Bradley Harris Dec 2015

Elucidating The Mechanisms Of Rate-Dependent Deformation At Ambient Temperatures In A Model Metallic Glass, Matthew Bradley Harris

Theses and Dissertations

In this work, the Shear Transformation Zone (STZ) dynamics model is adapted to capture the transitions between different regimes of flow serration in the deformation map of metallic glass. This was accomplished by scaling the STZ volume with a log-linear fit to the strain rate, and also adjusting the activation energy of an STZ with a log-linear fit to maintain constant yield strength at differing strain rates. Twelve simulations are run at each of six different strain rates ranging from 10-5 to 100 s-1, and statistics are collected on simulation behavior and shear band nucleation and …

Go to article

Effects Of Various Mobility Aids On Lower-Extremity Muscle Activity, Michael Ryan Sanders Dec 2015

Effects Of Various Mobility Aids On Lower-Extremity Muscle Activity, Michael Ryan Sanders

Theses and Dissertations

Millions of people each year spend some portion of their time using mobility aids to facilitate periods of non-weight bearing ambulation. The use of these devices changes the loading conditions of the lower extremities, which may result in skeletal muscle adaptations. The purpose of this work was to evaluate the effects of 3 types of mobility aids on lower-extremity muscle activity. Evaluation was based on 1) measured muscle activation signals using electromyography (EMG), and 2) measured joint kinematics and ground reaction forces, which were used to predict muscle forces. 16 healthy subjects (7 female, 9 male), ages 18-27 participated in …

Go to article

Underwater Rope Fatigue Testing Machine, Napoleon Nino, Andrew Pimentel Dec 2015

Underwater Rope Fatigue Testing Machine, Napoleon Nino, Andrew Pimentel

Mechanical Engineering

The design and fabrication of an underwater rope fatigue testing machine meant to simulate the effects of an oceanic environment and the effects on rope.

Go to article

First Prev Next Last