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Full-Text Articles in Engineering

Balsa Wood Bridge Senior Project, Ryan Moe Jan 2023

Balsa Wood Bridge Senior Project, Ryan Moe

All Undergraduate Projects

For all of human history, people have been working to increase efficiency. This project followed in that pursuit by forcing engineers to create a 400 mm long bridge out of only balsa wood and glue that could withstand over 20 kgs of force with the bridge weighing a maximum of only 85 grams. The bridge also needed to have a lifting mechanism to raise it 140 mm above the starting position.

To accomplish this task, a strong truss needed to be built. Balsa wood is strong in compression so a truss with more beams in compression was used. Statics was …


Thermodynamic Analysis Of A Novel Cycle For Nuclear Smr And Heat Transfer Performance Validation Of The Related Supercritical Working Fluids, Benjamin M. Pepper May 2022

Thermodynamic Analysis Of A Novel Cycle For Nuclear Smr And Heat Transfer Performance Validation Of The Related Supercritical Working Fluids, Benjamin M. Pepper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Currently, all operating nuclear power facilities in the U.S. follow the same general design and process: light-water reactors boil water into steam using bundles of nuclear fuel rods as a heat source, pumping that steam through a turbine which powers a generator to produce clean year-round electricity. Water is an effective coolant, but other facilities around the world have demonstrated the ability to use non-water-based coolants in nuclear reactor designs, which consequently have their own trade-offs. Some positive consequences of using different reactor designs include enhanced safety, better economics, and cheaper clean consumer energy. The work described in this paper …


A Multi Physics Integrated Solution For A High-Pressure Stage Turbine Efficiency And Durability, Sanjay Chopra Jul 2021

A Multi Physics Integrated Solution For A High-Pressure Stage Turbine Efficiency And Durability, Sanjay Chopra

Theses and Dissertations

World electricity demand is projected to grow at an annual rate of ~ 2.1% to year 2040₁. EIA projects nearly 50% increase in world energy usage by 2050 led by growth in Asia.[28];[29]. It is predicted that the global electricity demand grows at approximately 1.6 % per year from approximately 2008 and forecasted to approximately 2035, twice the rate of primary energy demand. This raises electricity's usage in total final energy consumption from approximately 19% in 2018 to approximately 24% in 2040. Electricity demand growth is set to be particularly strong in developing economies. .[28];[29];[38] As an enabler, to meet …


Development Of The Carbon Nanotube Thermoacoustic Loudspeaker, Troy Bouman Jan 2021

Development Of The Carbon Nanotube Thermoacoustic Loudspeaker, Troy Bouman

Dissertations, Master's Theses and Master's Reports

Traditional speakers make sound by attaching a coil to a cone and moving that coil back and forth in a magnetic field (aka moving coil loudspeakers). The physics behind how to generate sound via this velocity boundary condition has largely been unchanged for over a hundred years. Interestingly, around the time moving coil loudspeakers were first investigated the idea of using heat to generate sound was also known. These thermoacoustic speakers heat and cool a thin material at acoustic frequencies to generate the pressure wave (i.e. they use a thermal boundary condition). Unfortunately, when the thermoacoustic principle was initially discovered …


Atmospheric Water Harvester, Justin K. Lam, Jacob David, Jessica Mabry, Ben Brough Jun 2020

Atmospheric Water Harvester, Justin K. Lam, Jacob David, Jessica Mabry, Ben Brough

Mechanical Engineering

Atmospheric water harvesting uses the vapor-compression cycle to collect water from the moisture in the air. The system’s components include an evaporator, condenser, compressor, fan, and several expansion valves. Condensate from the air is then funneled into a receptacle, which determines the efficiency of the water harvesting system. For this senior project, the goal is to increase the efficiency of an existing atmospheric water harvester.


Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James Aug 2019

Isentropic Efficiency And Theoretical Analysis Of The Planetary Rotor Expander, Joseph L. James

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Expanders allow pressurized fluids to undergo a pressure decrease in a controlled environment via volumetric growth to extract fluid energy. There are many types of expanders, and the objective of this thesis is to model the efficiencies of the planetary rotor expander (PRE), a century-old design undeveloped due to insufficient manufacturing capabilities (until recently). Geometric relationships are derived and mathematical models are generated to determine the efficiency of the PRE as a function of design variables. Two industrially relevant case studies show that, to maximize isentropic efficiency, the planetary rotor expander (PRE) rotational frequency is maximized and rotor geometry optimized.


Analysis Of Distortion Transfer And Generation Through A Fan And A Compressor Using Full-Annulus Unsteady Rans And Harmonic Balance Approaches, Daniel Robert Soderquist Apr 2019

Analysis Of Distortion Transfer And Generation Through A Fan And A Compressor Using Full-Annulus Unsteady Rans And Harmonic Balance Approaches, Daniel Robert Soderquist

Theses and Dissertations

Understanding distortion transfer and generation through fan and compressor blade rows is able to assist in blade design and performance prediction. Using full annulus unsteady RANS simulations, the effects of distortion as it passes through the rotor of a transonic fan at five radial locations (10%, 30%, 50%, 70%, and 90% span) are analyzed. The inlet distortion profile is a 90-degree sector with a 15% total pressure deficit. Fourier distortion descriptors are used in this study to quantitatively describe distortion transfer and generation. Results are presented and compared for three operating points (near-stall, design, and choke). These results are used …


Electrathon Vehicle: Electrical Power, Samuel Johnson Jan 2019

Electrathon Vehicle: Electrical Power, Samuel Johnson

All Undergraduate Projects

The Electrathon Vehicle: Electrical Power proposal is an in depth dive into theorizing, constructing and testing the design of an electrical circuit. A breakdown of this report gives an extensive and thorough analysis of the problem. How do you efficiently deliver 1kw/hr of power to an electric motor? The methods used to face this challenge and the results seen after are laid out in this report.

The challenge of competing in the Electrathon Race is delivering power to an electric motor for an entire hour without exceeding 1kW/hr of power. The goal is to travel as much distance in the …


Dual-Axis Solar Tracker, Alazone Smith Jan 2019

Dual-Axis Solar Tracker, Alazone Smith

All Undergraduate Projects

The global energy crisis and continued supporting evidence of global climate change have begun to shift the world economies towards solutions that solve both challenges. Solar power has become one of the most recognizable and popularized renewable energy methods to date. In comparison to other photovoltaic systems, this project demonstrates the performance advantages of a dual-axis solar tracker. It also addressing its viability on a non-commercial scale. The objective was to improve upon previous solar tracker projects at Central Washington University by adding another axis to the system. This system implements both an actuator and a stepper motor to examine …


Trade-Off Balancing For Stable And Sustainable Operating Room Scheduling, Amin Abedini Jan 2019

Trade-Off Balancing For Stable And Sustainable Operating Room Scheduling, Amin Abedini

Theses and Dissertations--Mechanical Engineering

The implementation of the mandatory alternative payment model (APM) guarantees savings for Medicare regardless of participant hospitals ability for reducing spending that shifts the cost minimization burden from insurers onto the hospital administrators. Surgical interventions account for more than 30% and 40% of hospitals total cost and total revenue, respectively, with a cost structure consisting of nearly 56% direct cost, thus, large cost reduction is possible through efficient operation management. However, optimizing operating rooms (ORs) schedules is extraordinarily challenging due to the complexities involved in the process. We present new algorithms and managerial guidelines to address the problem of OR …


Development And Thermodynamic Analysis Of An Integrated Mild/Partial Gasification Combined Cycle (Impgc) Under Green And Brown Field Conditions With And Without Carbon Capture, Henry A. Long Iii Dec 2018

Development And Thermodynamic Analysis Of An Integrated Mild/Partial Gasification Combined Cycle (Impgc) Under Green And Brown Field Conditions With And Without Carbon Capture, Henry A. Long Iii

University of New Orleans Theses and Dissertations

Coal is a very prominent energy source in the world, but it is environmentally unattractive due to its high sulfur and ash content as well as its alleged contribution towards climate change, but it is affordable, abundant, and has high energy content. Thus, utilizing coal in a cleaner and more efficient way has become necessary. One promising clean coal technology involves fully gasifying coal into synthesis gas, cleaning it, and feeding it into a high-efficiency combined cycle, such as an Integrated Gasification Combined Cycle (IGCC). Inspired by the recent success of warn gas cleanup (WGCU), mild and partial gasification are …


Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi Dec 2018

Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi

Graduate Theses and Dissertations

This thesis compares the performance of a nine-level transformerless cascaded H-bridge (CHB) inverter with integrated battery energy storage system (BESS) using SiC power MOSFETs and Si IGBTs. Two crucial performance drivers for inverter applications are power loss and efficiency. Both of these are investigated in this thesis. Power devices with similar voltage and current ratings are used in the same inverter topology, and the performance of each device is analyzed with respect to switching frequency and operating temperature. The loss measurements and characteristics within the inverter are discussed. The Saber® simulation software was used for the comparisons. The power MOSFET …


Solar Electric Immersion Heating Element Fabrication, Logan V. Kregness Jun 2018

Solar Electric Immersion Heating Element Fabrication, Logan V. Kregness

Industrial and Manufacturing Engineering

Believing that cooking with flame is cheaper and more efficient than cooking with electricity, Ugandan citizens have exposed themselves to several health and safety risks, including major respiratory issues through harmful emissions, pollution, and the burning down of many homes. Even though solar electric cooking is cheaper and healthier than cooking with flames in the long run, many Ugandans lack the resources to invest in cooking with electricity.

The Solar Stove student research team, led by Dr. Pete Schwartz, partnered with Aid Africa to bring solar panels and prototype solar electric cooking units to villages in Uganda. Observing how their …


Reducing Overall Overtime Hours Accumulated By San Luis Sourdough, Marie Scholl, Emily Vallejos, Randall Yonce Jun 2018

Reducing Overall Overtime Hours Accumulated By San Luis Sourdough, Marie Scholl, Emily Vallejos, Randall Yonce

Industrial and Manufacturing Engineering

The packaging department of San Luis Sourdough Company was redesigned to increase bread throughput and decrease overtime hours issued to employees. Time studies were performed to get an accurate representation of the average throughput of bread with the current packaging conveyor system. After collecting data and surveying the employees and management, we came up with three design solutions to improve their current packaging system. The first design recommendation has a low-investment and is quick to implement as it pertains to changing the worker’s schedule to alleviate the employees from working long hour shifts while increasing the bread throughput. The second …


Healing Alternatives Workspace Remodel, Lissandra Ilcyn, Jenifer Astrid Colmenares, Grace E. Kuffner Jun 2018

Healing Alternatives Workspace Remodel, Lissandra Ilcyn, Jenifer Astrid Colmenares, Grace E. Kuffner

Industrial and Manufacturing Engineering

Healing Alternatives is an acupuncture office space located in a repurposed house in San Luis Obispo. Healing Alternatives’ current facility layout does not allow for an additional treatment room or the space to provide additional services because of the wasted space within the facility. Furthermore, patients can be disrupted by noise outside the treatment room causing a negative customer experience. The project team’s objectives are to:

o Design two layout alternatives

o Provide a time estimate for each alternative

o Provide a cost analysis of each alternative

o Implement 5s methodology on the storage room

o Provide a 2D-3D model …


Improving Efficiencies For The Loading And Packaging Departments At San Luis Sourdough, Alexis Bergstrom, Isabella Pereira, Claudia Robinson Jun 2018

Improving Efficiencies For The Loading And Packaging Departments At San Luis Sourdough, Alexis Bergstrom, Isabella Pereira, Claudia Robinson

Industrial and Manufacturing Engineering

San Luis Sourdough, currently has issues with efficiency and standardization in their packaging department, ergonomics problems in the packaging department, shipment accuracy in their loading department, and lacks an organized layout design. As a result, four objectives were designed within a six month period. The first was to create standard operating procedures for the packaging department. To inform this decision time studies were performed before and after creating these SOPs. It was discovered that there was a clear need for the SOPs due to variation in packaging efficiency among new and experienced associates. The second set of time studies showed …


The Design Of A Digital Scheduling Solution For Healing Alternatives, Hailey A. Malin, Krista L. Mcallester, Anne E. Shields Jun 2018

The Design Of A Digital Scheduling Solution For Healing Alternatives, Hailey A. Malin, Krista L. Mcallester, Anne E. Shields

Industrial and Manufacturing Engineering

The focus of this senior project is to assist Healing Alternatives, an acupuncture clinic located in San Luis Obispo, in developing a business management software to fit their needs and boost their overall organization. The approach to finding the right fit for this business included assessing their current system while simultaneously investigating other providers. Once alternatives were found that met all of Healing Alternatives’ initial requirements, trial demos were generated in order to perform user experience testing. The presented final solution, a scheduling software called Acuity Scheduling, was implemented in a three-phase move plan that occurred over the period of …


Slm Materials Development, Justin G. Reiner, Michael T. Schembri Jun 2018

Slm Materials Development, Justin G. Reiner, Michael T. Schembri

Industrial and Manufacturing Engineering

The purpose of this project was to create a procedure to efficiently determine a “recipe” of parameter values that create a desired set of mechanical properties. Research was conducted into the laser powder bed fusion process with focus on underdeveloped materials. A design of experiment was used with a set of density correlated parameters to establish a method of producing nearly dense parts. Our methods include SLM printing, metrology, and statistical analysis. An experimental procedure for materials development was designed, but unable to be validated during the scope of this project, due to unforeseen safety issues (exposure to Chromium 6, …


Cal Poly Supermileage Drivetrain, Michael Bolton, Justin Miller, Heather Fields Jun 2018

Cal Poly Supermileage Drivetrain, Michael Bolton, Justin Miller, Heather Fields

Mechanical Engineering

The following report details the full design process used by the Cal Poly Supermileage Drivetrain (CPSMD) Senior Project team in designing a new drivetrain system for the Cal Poly Supermileage Vehicle (SMV) Team. Included is the development stages of each component, the manufacturing of our parts, the final solution’s assembly, the testing of the project, and the results from the 2018 Shell Eco-Marathon Competition. After collecting data from several tests, only the final drivetrain efficiency and final sprocket alignment remain unknown. Otherwise, the project came in under budget, within our weight tolerance, and met all the other design objectives. The …


Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney Jan 2018

Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney

Graduate Theses, Dissertations, and Problem Reports

Decentralized power generation is a research area of interest due to possible improvements in electrical generation efficiency and grid resilience. Two-stroke engines are simple, inexpensive, power dense systems that could serve as the prime-movers for combined heat and power (CHP) systems. In addition, such systems could be fueled on natural gas (NG) that is readily available to serve as a reliable fuel source in most households. However, most two-stroke engines are inefficient and produce excessive emissions. This research focused on methods to simultaneously improve engine efficiency and decrease emissions from a 34 cc air-cooled, two-stroke engine retrofitted to operate on …


Improving The Efficiency Of Wind Farm Turbines Using External Airfoils, Shujaut Bader Oct 2017

Improving The Efficiency Of Wind Farm Turbines Using External Airfoils, Shujaut Bader

Masters Theses

Wind turbine efficiency typically focuses on the shape, orientation, or stiffness of the turbine blades. In this thesis, the focus is instead on using static fixed airfoils in proximity to the wind turbine to control the airflow coming out of the turbine. These control devices have three beneficial effects. (1) They gather air from “higher up” where the air is moving faster on average (and therefore has more kinetic energy in it). (2) They throw the used (and slowed down air) downwards. This means that any turbines in the wind farm behind the lead turbines do not get “stale” air. …


Design For Waste Reduction And Efficiency Improvement For The Construction Usage Of The Tower Crane, George Merida, Roman Richard Jun 2017

Design For Waste Reduction And Efficiency Improvement For The Construction Usage Of The Tower Crane, George Merida, Roman Richard

Industrial and Manufacturing Engineering

Webcor Concrete Group’s on-site tower crane is currently experiencing unknown forms of inefficiency. The project team used the DMAIC methodology to implement Define, Measure, Analyze, Improve, and Control in order to guide and structure the project. After the project team formulated a problem statement, observations were collected of tower crane deliveries resulting in 470 individual data points. The data was then analyzed using basic statistics, histograms, and lean manufacturing tools in order to identify wastes and inefficiencies. Once the wastes and inefficiencies were identified, root cause analysis was performed. The identified root causes were then used as the basis for …


Optimization Methodology For Cvt Ratio Scheduling With Consideration Of Both Engine And Cvt Efficiency, Steven Beuerle Dec 2016

Optimization Methodology For Cvt Ratio Scheduling With Consideration Of Both Engine And Cvt Efficiency, Steven Beuerle

Masters Theses

A transmission ratio schedule is developed to optimize the fuel consumption for an automotive continuously variable transmission (CVT) connected to an internal combustion engine (ICE). Although the optimal operating line (OOL) generated from an engine brake specific fuel consumption (BSFC) map can be used to generate a CVT ratio schedule that yields maximum engine efficiency, it was found that OOL-based CVT ratio scheduling does not necessarily offer the best fuel economy because optimal CVT efficiency does not always correspond to OOL tracking. To develop a CVT ratio schedule that can offer the best fuel economy, a novel ratio-scheduling methodology is …


Investigation Of Digital Pump/Motor Control Strategies, Farid El Breidi Aug 2016

Investigation Of Digital Pump/Motor Control Strategies, Farid El Breidi

Open Access Dissertations

A pump is the heart of fluid power systems, it has a significant impact on the efficiency of many fluid power systems. Motors are the most common rotary actuators in fluid power systems. State-of-the-art pump/motor units can achieve efficiencies higher than 90% when operating at maximum displacement; however, as the displacement drops, the efficiency of these units drops to below 50%. A new digital pump/motor design aims at increasing these efficiencies by utilizing two electrically controlled high speed on/off valves per displacement chamber; these valves provide the ability to achieve variable displacement and allow freedom in choosing operating strategies. Such …


Haas Automation Umc750 5axis Mill Assembly Process Improvement, Mason A. Garcia, Gregory R. Gunion, Juan Pablo Quinonez Weston Jun 2016

Haas Automation Umc750 5axis Mill Assembly Process Improvement, Mason A. Garcia, Gregory R. Gunion, Juan Pablo Quinonez Weston

Industrial and Manufacturing Engineering

The improvement of the current assembly of the motor and casting components for the Haas UMC-750 5-Axis vertical CNC mill includes the evaluation, development and proposal of a new pair of material handling carts. To meet these deliverables, a student team began by assessing the assembly workstation, defining the problem to be solved, researching ergonomics in material handling equipment and drafting the final design of the improved cart models using SolidWorks. The final design considered the initial improvement request from the client, as well as better ergonomic features to enhance the safety of the operators. It was estimated that the …


Efficiency Testing Of An Electronic Speed Controller, Grace Cowell, Matthew Hudson, Marcus Pereira Jun 2016

Efficiency Testing Of An Electronic Speed Controller, Grace Cowell, Matthew Hudson, Marcus Pereira

Mechanical Engineering

This project required the development of a rig that could experimentally determine the efficiency of an Electronic Speed Controller (ESC). The selected design focuses on measuring the losses due to heat from the device and comparing this to its input power. The selected design is a flow rig that utilizes the heat equation q=ṁcpΔT. The rig provides a steady state measurement of the ESC heat output by passing a known mass flow rate of air across the ESC and measuring the temperature difference. It uses a flowmeter to determine ṁ, thermocouples to determine ΔT, and a table lookup to determine …


Efficiency Evaluation Of A Magnetically Driven Multiple Disk Centrifugal Blood Pump, Kayla H. Moody Jan 2016

Efficiency Evaluation Of A Magnetically Driven Multiple Disk Centrifugal Blood Pump, Kayla H. Moody

Theses and Dissertations

Heart failure is expected to ail over 8 million people in America by 2030 leaving many in need of cardiac replacement. To accommodate this large volume of people, ventricular assist devices (VADs) are necessary to provide mechanical circulatory support. Current VADs exhibit issues such as thrombosis and hemolysis caused by large local pressure drops and turbulent flow within the pump. Multiple disk centrifugal pumps (MDCPs) use shearing and centrifugal forces to produce laminar flow patterns and eliminate large pressure drops within the pump which greatly reduce risks that are in current VADs. The MDCP has a shaft drive system (SDS) …


Modeling And Test Of The Efficiency Of Electronic Speed Controllers For Brushless Dc Motors, Clayton R. Green Sep 2015

Modeling And Test Of The Efficiency Of Electronic Speed Controllers For Brushless Dc Motors, Clayton R. Green

Master's Theses

Small electric uninhabited aerial vehicles (UAV) represent a rapidly expanding market requiring optimization in both efficiency and weight; efficiency is critical during cruise or loiter where the vehicle operates at part power for up to 99% of the mission time. Of the four components (battery, motor, propeller, and electronic speed controller (ESC)) of the electric propulsion system used in small UAVs, the ESC has no accepted performance model and almost no published performance data. To collect performance data, instrumentation was developed to measure electrical power in and out of the ESC using the two wattmeter method and current sense resistors; …


Improved Methods For Identifying, Applying, And Verifying Industrial Energy Efficiency Measures, Andrew Chase Harding May 2015

Improved Methods For Identifying, Applying, And Verifying Industrial Energy Efficiency Measures, Andrew Chase Harding

Graduate Theses and Dissertations

Energy efficiency is the least expensive source of additional energy capacity for today's global energy expansion. Energy efficiency offers additional benefits of cost savings for consumers, reduced environmental impacts, and enhanced energy security. The challenges of energy efficiency include identifying potential efficiency measures, quantifying savings, determining cost effectiveness, and verifying savings of installed measures. This thesis presents three separate chapters which address these challenges. The first is a paper presented at the 2014 industrial energy technology conference (IETC) that details a compressed air system project using the systems approach to identify cost effective measures, energy intensity to project savings, and …


Increasing Efficiency Of Thermal Desalination, Jarrod A. Edwards, Mackinzie Washington, Chan Jung, Ben Garrison Jan 2015

Increasing Efficiency Of Thermal Desalination, Jarrod A. Edwards, Mackinzie Washington, Chan Jung, Ben Garrison

Chancellor’s Honors Program Projects

No abstract provided.