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Full-Text Articles in Mechanical Engineering

Existing Methods For Monitoring Power Autotransformers, Nurali Berdiyorovich Pyrmatov, Dilafruz Rustamjon Qizi Abdullabekova Jan 2024

Existing Methods For Monitoring Power Autotransformers, Nurali Berdiyorovich Pyrmatov, Dilafruz Rustamjon Qizi Abdullabekova

Technical science and innovation

autotransformers, methods, diagnostics, efficiency, monitoring.Particular attention is given to analyzing the gas composition of transformer oil, which is a sensitive indicator of various defects such as thermal breakdown and heating. In addition, methods based on the measurement of external magnetic field strength are discussed. This technique provides a unique opportunity to detect magnetic anomalies associated with possible defects in the structural components of the transformer. The article emphasizes that successful monitoring requires an integrated approach, combining different techniques. The authors analyze the advantages and limitations of each method and offer practical recommendations for integrating these methods into maintenance systems. In …


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 …


Mathematical Model Of The Efficiency Of Investments Aimed In The Implementation Of Water-Saving Technologies Dec 2021

Mathematical Model Of The Efficiency Of Investments Aimed In The Implementation Of Water-Saving Technologies

Irrigation and Melioration

In Uzbekistan, research work is being carried out aimed at improving the economic mechanisms for the introduction of water-saving technologies for irrigating agricultural crops. At the same time, the issues related to the analysis of the effectiveness of the use of water-saving technologies when irrigating cotton, the development of mathematical methods for assessing the effectiveness of investments, as well as their introduction into practice have not been sufficiently studied. This article provides a mathematical model of the efficiency of investments aimed at introducing water-saving technologies. The results of a numerical experiment of a mathematical model show that the introduction of …


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 …


Double-Acting Batch Reverse Osmosis Configuration For Best-In-Class Efficiency And Low Downtime, Sandra Cordoba, Abhimanyu Das, Jorge Leon, Jose M. Garcia, David M. Warsinger Jun 2021

Double-Acting Batch Reverse Osmosis Configuration For Best-In-Class Efficiency And Low Downtime, Sandra Cordoba, Abhimanyu Das, Jorge Leon, Jose M. Garcia, David M. Warsinger

School of Mechanical Engineering Faculty Publications

Energy consumption in reverse osmosis has decreased substantially over the last few decades thanks to the implementation of energy recovery devices, high efficiency pumps, and improved membranes. However, to further increase the adoption of the technology, its energy needs must still be reduced. Batch and semi-batch reverse osmosis configurations have shown potential to be the most energy efficient reverse osmosis variants, but have remaining inefficiencies from brine mixing and high downtime. In this study, we modeled in new detail a further improved double-acting batch reverse osmosis system that uses a high-pressure tank with a reciprocating piston. A high-pressure pump is …


Efficiency Of A Helio Heating Collector, Azamat Usenov, Shaxnoza Sultanova Phd, Jasur Safarov Dr., Professor, Tojiniso Rahmanova Mar 2021

Efficiency Of A Helio Heating Collector, Azamat Usenov, Shaxnoza Sultanova Phd, Jasur Safarov Dr., Professor, Tojiniso Rahmanova

Technical science and innovation

A study of several industrial heat demand identified several industries with favourable conditions for the use of solar energy, the most important industrial processes using heat at moderate temperatures are: sterilization, pasteurization, drying, hydrolysis, distillation and evaporation, rinsing and cleaning and polymerization. The study describes some important processes and the temperature range required for each of them.

In this paper, a model of a solar water-heated drying device for drying ginger (Zungiber) root and other medicinal plants has been developed and studied experimentally. Using the model, the useful energy and temperature coming from the solar collector were analysed. The graphs …


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 …


Empirical Assessment Of Climate Change Impacts On Agriculture In Samarkand Region, Sh.B. Babakholov Dec 2020

Empirical Assessment Of Climate Change Impacts On Agriculture In Samarkand Region, Sh.B. Babakholov

Irrigation and Melioration

Agricultural production is highly sensitive to climate factors like other endogenous factors, and the expected climate change projections may have a negative impact on the efficiency and income of agricultural producers. Therefore, this study aims to analyze the impact of changes in climatic factors (average air temperature and precipitation) on the technical efficiency of cotton growing farmers as its determinants in Samarkand region. Empirical analyzes were performed on the cases of 1141 cotton-growing farms using panel-based Time-Invariant Inefficiency model. According to the results of the analysis, cotton farms in the region have an average technical efficiency of 76%, which in …


The Energy And Exergy Of Light With Application To Societal Exergy Analysis.Pdf, Matthew K. Heun, Zeke Marshall, Emmanuel Aramendia, Paul E. Brockway Oct 2020

The Energy And Exergy Of Light With Application To Societal Exergy Analysis.Pdf, Matthew K. Heun, Zeke Marshall, Emmanuel Aramendia, Paul E. Brockway

University Faculty Publications and Creative Works

Lighting provides an indispensable energy service, illumination. The field of societal exergy analysis considers light (andmany other energy products) to be enablers of economic growth, and lighting contributes a non-negligible proportion of total useful exergy supplied to modern economies. In societal exergy analysis, the exergetic efficiency of electric lamps is central to determining the exergy contribution of lighting to an economy. Conventionally, societal exergy practitioners estimate the exergetic efficiency of lamps by an energy efficiency, causing confusion and, sometimes, overestimation of exergetic efficiency by a factor as large as 3. In response, we use recent results from the fields of …


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.


Study Of Zno Nanospheres Fabricated Via Thermal Evaporation For Solar Cell Application, Fatin Farisha Alia Azmi, Bouchta Sahraoui, Saifful Kamaluddin Muzakir Apr 2019

Study Of Zno Nanospheres Fabricated Via Thermal Evaporation For Solar Cell Application, Fatin Farisha Alia Azmi, Bouchta Sahraoui, Saifful Kamaluddin Muzakir

Makara Journal of Technology

A solar cell is a device that absorbs light energy to generate electrical energy. A typical example of a solar cell is the quantum dot solar cell (QDSC), which consists of three main components: (i) fluorophore: the component that absorbs light and generates excited state electrons and holes, (ii) photoelectrode: the component that transports the excited state electron and prevents recombination of excited state electrons and holes, and (iii) electrolyte: the component that re-plenishes the vacancy left by the excited electron in the hole. Despite the increasing number of research in the QDSC field, to date, a device with significant …


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 …


Enhancing Heat Pipe Solar Water Heating Systems Performance Using A Novel Variable Mass Flow Rate Technique And Different Solar Working Fluids, Abdellah Shafieian, Junaid Jaffer Osman, Mehdi Khiadani, Ataollah Nosrati Jan 2019

Enhancing Heat Pipe Solar Water Heating Systems Performance Using A Novel Variable Mass Flow Rate Technique And Different Solar Working Fluids, Abdellah Shafieian, Junaid Jaffer Osman, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

This paper aims to improve the overall efficiency of heat pipe solar water heating (HPSWH) systems by implementing a novel variable mass flow rate technique which regulates the solar working fluid mass flow rate of the system with the solar radiation intensity. To analyse the system under real operational conditions, the residential hot water consumption pattern of Perth residents in Western Australia was used in the experiments. In addition, a nanofluid (Al2O3/DI) was fabricated and its performance as the solar working fluid was investigated to find the optimum concentration and to confirm its stability and thermo-physical …


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 …


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 …


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 …


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, …


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 …


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 …


Electrical Response Of Thermoelectric Generator To Geometry Variation Under Transient Thermal Boundary Condition, Elias Yazdanshenas, Alireza Rezania, Meysam Karami Rad, Lasse Rosendahl Jan 2018

Electrical Response Of Thermoelectric Generator To Geometry Variation Under Transient Thermal Boundary Condition, Elias Yazdanshenas, Alireza Rezania, Meysam Karami Rad, Lasse Rosendahl

Mechanical & Aerospace Engineering Faculty Publications

A three-dimensional numerical model is applied in this study to illustrate the electrical response of a thermoelectric generator (TEG) during transient heat flux at the hot side. In this work, various types of thermal boundary conditions are considered to evaluate the performance of the TEG. Thus, a TEG under pulsed heat flux is studied numerically, and the numerical model is verified by experimental results. With the consideration of a defined reference geometry, different heat flux frequencies are applied in order to evaluate the corresponding electrical output by the TEG. In addition, variation of the module performance for various TEG leg …


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 …


A Review Of Latest Developments, Progress, And Applications Of Heat Pipe Solar Collectors, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati Jan 2018

A Review Of Latest Developments, Progress, And Applications Of Heat Pipe Solar Collectors, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

Among all the available solutions to the current high energy demand and consequent economic and environmental problems, solar energy, without any doubt, is one of the most promising and widespread solutions. However, conventional solar systems face some intractable challenges affecting their technical performance and economic feasibility. To overcome these challenges, increasing attention has been drawn towards the utilization of heat pipes, as an efficient heat transfer technology, in conventional solar systems. To the authors’ knowledge, despite many valuable studies on heat pipe solar collectors (mainly during the last decade), a comprehensive review which surveys and summarizes those studies and identifies …