Mechanical Engineering Commons^™

Infinite Photovoltaic Solar Arrays: Considering Flux Of Momentum And Heat Transfer, Andrew D. S. Glick

Dissertations and Theses

Large scale solar farms supply an increasing amount of the worlds electricity supply. However, in order to reach cost parity with fossil fuels, further reductions are necessary. Towards this end, photovoltaic (PV) panel cooling becomes increasingly important; high temperatures both decrease efficiency and panel lifetime. To better understand, characterize, and exploit the natural convective cooling of utility scale solar farms, a model solar farm was created. Using both thermal measurements and particle image velocimetry to characterize heat transfer and velocity fields, wind tunnel experiments were conducted using the model solar farm. Three parameters were examined for their effect on heat …

Non-Einstein Viscosity Phenomenon Of Acrylonitrile–Butadiene–Styrene Composites Containing Lignin–Polycaprolactone Particulates Highly Dispersed By High-Shear Stress, Sing-Hoon Kim, Kisuk Choi, Kyouk Ryeol Choi, Taesung Kim, Jonghwan Suhr, Kwang Jin Kim, Hyoung Jin Choi, Jae-Do Nam

Mechanical Engineering Faculty Research

Lignin powder was modified via ring-opening polymerization of caprolactone to form a lignin–polycaprolactone (LPCL) particulate. The LPCL particulates were mixed with an acrylonitrile–butadiene–styrene (ABS) matrix at an extremely high rotational speed of up to 3000 rpm, which was achieved by a closed-loop screw mixer and in-line melt extruder. Using this high-shear extruding mixer, the LPCL particulate size was controlled in the range of 3395 nm (conventional twin-screw extrusion) down to 638 nm (high-shear mixer of 3000 rpm) by altering the mixing speed and time. The resulting LPCL/ABS composites clearly showed non-Einstein viscosity phenomena, exhibiting reduced viscosity (2130 Pa·s) compared to …

Biomethane Production From Distillery Wastewater, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Distillery wastewater treatment is a great ecological problem, for example, India produces 2.7 billion liters of alcohol that results in 40 billion liters of wastewater. However, this material can be seen as a resource since 11 million cubic meters of biogas at 60% methane could be produced in addition to cleaning the water. The distillery has two options of what to do with the biogas. The first is to use the biogas to fuel the distillery making the production plant more energy efficient and removing some of the need to buy natural gas. The other is to upgrade the biogas …

Optimization Of Induction Quenching Processes For Hss Roll Based On Mmpt Model, Ligang Liu, Hui Yu, Zhiqiang Yang, Chunmei Zhao, Tongguang Zhai

Chemical and Materials Engineering Faculty Publications

To improve the comprehensive performance of high speed steel (HSS) cold rolls, the induction hardening processes were analyzed by numerical simulation and experimental research. Firstly, a modified martensitic phase transformation (MMPT) model of the tested steel under stress constraints was established. Then, the MMPT model was fed into DEFORM to simulate the induction quenching processes of working rolls based on an orthogonal test design and the optimal dual frequency of the induction quenching process was obtained. The results indicate that the depth of the roll’s hardened layer increases by 32.5% and the axial residual tensile stress also becomes acceptable under …

Mapping Modeled Exposure Of Wildland Fire Smoke For Human Health Studies In California, Patricia Koman, Michael Billmire, Kirk Baker, Ricardo De Majo, Frank Anderson, Sumi Hoshiko, Brian Thelen, Nancy H. F. French

Michigan Tech Publications, Part 1

Wildland fire smoke exposure affects a broad proportion of the U.S. population and is increasing due to climate change, settlement patterns and fire seclusion. Significant public health questions surrounding its effects remain, including the impact on cardiovascular disease and maternal health. Using atmospheric chemical transport modeling, we examined general air quality with and without wildland fire smoke PM_2.5. The 24-h average concentration of PM_2.5 from all sources in 12-km gridded output from all sources in California (2007–2013) was 4.91 μg/m³. The average concentration of fire-PM_2.5 in California by year was 1.22 μg/m³ (~25% …

Transient Flow Analysis Of A Closing Blowout Preventer Using Computational Fluid Dynamics (Cfd), Daniel Barreca

LSU Master's Theses

Reliability of blowout preventers (BOPs) is crucial for drilling and production operations. Erosion of BOP components and hydrodynamic forces on rams may cause failure of BOP elements to seal the well. Transient computational fluid dynamics (CFD) simulations of fluids within the wellbore and BOP offer quantitative and qualitative data related to this reliability during the closure of various BOP components. Since limited research has been published in transient CFD simulations of closing BOPs, this thesis discusses challenges and solutions to simulating closing blowout preventers. Single component fluids are simulated through several BOP geometries such as annular preventers, pipe rams, and …

A Low-Cost Experimental Testbed For Multi-Agent System Coordination Control, Victor Fernandez-Kim

LSU Master's Theses

A multi-agent system can be defined as a coordinated network of mobile, physical agents that execute complex tasks beyond their individual capabilities. Observations of biological multi-agent systems in nature reveal that these ``super-organisms” accomplish large scale tasks by leveraging the inherent advantages of a coordinated group. With this in mind, such systems have the potential to positively impact a wide variety of engineering applications (e.g. surveillance, self-driving cars, and mobile sensor networks). The current state of research in the area of multi-agent systems is quickly evolving from the theoretical development of coordination control algorithms and their computer simulations to experimental …

Maximizing And Modeling Malonyl-Coa Production In Escherichia Coli, Tatiana Thompson Silveira Mello

LSU Master's Theses

In E. coli, fatty acid synthesis is catalyzed by the enzyme acetyl-CoA carboxylase (ACC), which converts acetyl-CoA into malonyl-CoA. Malonyl-CoA is a major building block for numerous of bioproducts. Multiple parameters regulate the homeostatic cellular concentration of malonyl-CoA, keeping it at a very low level. Understanding how these parameters affect the bacterial production of malonyl-CoA is fundamental to maximizing it and its bioproducts. To this end, competing pathways consuming malonyl-CoA can be eliminated, and optimal nutritional and environmental conditions can be provided to the fermentation broth. Most previous studies utilized genetic modifications, expensive consumables, and high-cost quantification methods, making …

Hydrogen Fuel Cell Vehicles; Current Status And Future Prospect, Yogesh Manoharan, Seyed Ehsan Hosseini, Brayden Butler, Hisham Alzhahrani, Bhi Thi Fou Senior, Turaj Ashuri, John Krohn

Faculty Publications - Mechanical Engineering

The hazardous effects of pollutants from conventional fuel vehicles have caused the scientific world to move towards environmentally friendly energy sources. Though we have various renewable energy sources, the perfect one to use as an energy source for vehicles is hydrogen. Like electricity, hydrogen is an energy carrier that has the ability to deliver incredible amounts of energy. Onboard hydrogen storage in vehicles is an important factor that should be considered when designing fuel cell vehicles. In this study, a recent development in hydrogen fuel cell engines is reviewed to scrutinize the feasibility of using hydrogen as a major fuel …

Residential Attic Performance Comparison Research, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

This research project evaluated cooling energy and moisture-related impacts between conventional attic venting and sealed attic vents in a lab home located in central Florida. All tests had R30 insulation on the ceiling and the roof deck uninsulated. A total of four different test configurations were tested. The four tested configurations were: Attic Vented with Attic Ducts, Attic Vents Sealed with Attic Ducts, Attic Vented with Indoor Ducts, and Attic Vents Sealed with Indoor Ducts. On average the impact from sealing attic vents will increase annual cooling energy use in a Florida home between 5%-10%. For a 1620 square foot …

The Seedling Sanctuary: Automated Cold Frame For Gardner Elementary, Fiona Bell, Christopher Carpio, Alex Kosaka

Mechanical Engineering Senior Theses

The purpose of this report is to provide the details of the Seedling Sanctuary, a mechanical engineering senior design project. The project in question is an automated cold frame designed specifically for Gardner Academy, a local elementary school in San Jose. A cold frame is a miniature greenhouse that opens like a chest and is made from clear plastic. Automated ventilation and watering systems create a microclimate within this greenhouse structure to create the ideal growing conditions for seeds. The main purposes of the cold frame are to lengthen the growing season, be maintenance free, and enhance garden education. From …

Cisco Nexus 9200 Robustness Redesign, Colin Berge, Ethan Gold, Cole Christopherson, Rahul Makhijani

Industrial and Manufacturing Engineering

Certain configurations of Cisco's Nexus 9200 product experienced issues with bending during shipping. Two solutions were developed to eliminate this problem: an external brace that could quickly address the problem yet was expensive and unsustainable, and a redesigned chassis, which was more economical but came with a longer time to implement. Real world packaging and shipping conditions were simulated in SolidWorks and Finite Element Analysis was used to model the stresses experienced when the product is dropped. Both designs were found to significantly reduce stress in critical areas, thus reducing the chance of failure and the cost of the problem. …

Quantifying Appearance For Opaque Surfaces Using Spectral Bidirectional Reflectivity, Christopher Richard Brooks

Theses and Dissertations

Quantifying the appearance of a surface is an important aspect in quality control. Becauseobjects at room temperature emit negligible amounts of radiation into the visible spectrum, aspectsof their appearance may be quantified using reflected light. Therefore, the appearance of opaquesurfaces may be quantified using measurements of the spectral, bidirectional reflectivity. However,measuring the spectral, bidirectional reflectivity of even one point at every set of incident andreflected directions is a time intensive process that is infeasible for quality control.The objective of this work was to determine whether a limited number of spectral, bidirectionalreflectance measurements may be used to characterize the appearance of …

Heat: Hydraulic And Electric Animation Team, Tyler J. Couvrette, Michael J. Cain, Sara T. Novell, Dexter K. Yanagisawa

Mechanical Engineering

Each New Years’ Day, the Cal Poly Rose Float presents a flower-covered float to the world at the Tournament of Roses parade. This floral display, paired with moving mechanical animations, shows off Cal Poly to the world. This project strove to keep Cal Poly on the cutting edge of technology both in parade floats, and in engineering, by creating a completely electric-powered animation system.

To accomplish this, a group of students set out to make the fully electric animation system that can power both the hydraulic and electric mechanisms on the Float. This was accomplished through months of planning and …

Fluid Power Vehicle Challenge - The Incompressibles - Final Design Report, Nicholas Gholdoian, Russell Posin, David Vitt, Alex Knickerbocker, Kyle Franck, Julian Rodkiewicz

Mechanical Engineering

This report provides a comprehensive description of the research, analysis and design work that The Incompressibles have completed thus far in the senior project process. This document includes all the work that The Incompressibles have completed for the team’s Preliminary Design Review (PDR), Critical Design Review (CDR), the work leading up to the 2019 FPVC competiton and the competition results. This report includes the initial research that the team completed for the fluid power competition, first iterations of designs, final iterations of designs, manufacturing results and processes, and finally testing and results from competition. With a new design for the …

Insulated Solar Electric Cooker Immersion Heater, Emily Burnside, Kaeley Dicks, Joshua R. Stevens, Brady Banks

Mechanical Engineering

This report is the final design review (FDR) report for our team completing the Insulated Solar Electric Cooker (ISEC) Immersion Heater mechanical engineering senior project. The goal of this project is to standardize and perform analysis on a preexisting, inexpensive solar-powered immersion heater for cooking use in developing countries, reducing the adverse effects presented by traditional biomass cooking fires. We also designed a manufacturing process to improve repeatability and to reduce labor investment of heater production. The ISEC research team from the California Polytechnic State University Physics Department have been working on the development of this immersion heater and have …

Estimation Of The Region Of Attraction Of Underactuated Systems And Its Enlargement Using Impulsive Inputs, Nilay Kant, Ranjan Mukherjee, Dhrubajit Chowdhury, Hassan K. Khalil

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Stabilization of an equilibrium point is an important control problem for underactuated systems. For a given control design, the ability of the system to remain stable in the presence of disturbances depends on the size of the region of attraction of the stabilized equilibrium. The sum of squares and trajectory reversing methods are combined together to generate a large estimate of the region of attraction. Then, this estimate is effectively enlarged by applying the impulse manifold method, which can stabilize equilibria from points lying outside the estimated region of attraction. In this paper, the generality of the approach is demonstrated …

Generation Of Nondiffracting Vector Beams With Ring-Shaped Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Nondiffracting Bessel, Mathieu, and Weber vector beams are generated by using ring-shaped plasmonic geometric metasurfaces. The nondiffracting vector beam is produced by the superposition of two off-axis right-handed and left-handed circularly polarized nondiffracting scalar beams described by the Whittaker integral, which are simultaneously generated by a single metasurface with the ring-shaped phase profile. The polarization states of the generated nondiffracting vector beams are analyzed by the Stokes parameters and the orbital angular momentum states are measured by the beam interference. In addition, the selfhealing properties of nondiffracting vector beams are further demonstrated, showing that not only the beam profiles but …

A Methodology For Verification Of Structural Standards For A Seating System By Finite Element Analysis, Zachary Kelly Dworaczyk Wiltshire

Master's Theses

Currently California Polytechnic State University has a patent pending on a new type of seating system designed to increase the functionality of public transportation vehicles. The patent is based on the work completed by a senior project group in 2016, whose design showcased the feasibility of the idea. Further development was completed by a second senior project group, the Adjustable Seating Systems, in 2019. The intent of the Adjustable Seating Systems group was to develop a seating system with the intent of commercialization and implementation in paratransit vehicles with future development into large buses and trains.

Seating systems used in …

Statistical Optimization Of Stress Level In Mg-Li-Al Alloys Upon Hot Compression Testing, Rezawana Islam, Meysem Haghshenas

Mechanical Engineering Faculty Publications

In the present study, a response optimization method using Extreme Vertices Mixer Design (EVMD) approach is proposed for stress optimization in a thermomechanically processed Mg-Li-Al alloy. Experimentation was planned as per mixed design proportions of Mg, Li and Al and process variables (i.e. temperature and strain rate). Each experiment has been performed under different conditions of factors proportions and process variables. The response, particularly stress has been considered for each experiment. The response is optimized to find an optimum condition when the contributing factors influence material characteristics in such a way, to achieve better strength, ductility and corrosion resistance. Estimated …

Analysis Of Geometric Accuracy And Thickness Reduction In Multistage Incremental Sheet Forming Using Digital Image Correlation, Mercedes M. Gonzalez, Nathan A. Lutes, Joseph D. Fischer, Mitchell R. Woodside, Douglas A. Bristow, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Incremental Sheet Forming (ISF) is a freeform manufacturing method whereby a 3D geometry is created by progressively deforming a metal sheet with a single point tool following a defined trajectory. The thickness distribution of a formed part is a major consideration of the process and is believed to be improved by forming the geometry in multiple stages. This paper describes a series of experiments in which truncated cone geometries were formed using two multistage methods and compared to the same geometry formed using the traditional single stage method. The geometric accuracy and thickness distributions, including 3D thickness distribution plots, of …

Iterative Learning Control Of Single Point Incremental Sheet Forming Process Using Digital Image Correlation, Joseph D. Fischer, Mitchell R. Woodside, Mercedes M. Gonzalez, Nathan A. Lutes, Douglas A. Bristow, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Single Point Incremental Sheet Forming (SPIF) is a versatile forming process that has gained significant traction over the past few decades. Its increased formability, quick part adaption, and reduced set-up costs make it an economical choice for small batch and rapid prototype forming applications when compared to traditional stamping processes. However, a common problem with the SPIF process is its tendency to produce high geometric error due to the lack of supporting dies and molds. While geometric error has been a primary focus of recent research, it is still significantly larger for SPIF than traditional forming processes. In this paper, …

Nanoparticle Injector For Photonic Manipulators Using Dielectrophoresis, Jaykob Maser, Joshua Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We describe the concept of a dielectrophoretic nanoparticle injector and its use in a plasmonic/photonic-based nanoparticle manipulation system. Particle motion is achieved by generating an electrostatic, non-uniform field between two tilted plates and applying the corresponding dielectrophoretic force to net-neutral nanoparticles. We investigate the dependence the dielectrophoretic force has on the plate angle of the charged plates as well as their separation distance, dielectric filler material, and exit interface membrane. Our results indicate an increasing average and maximum dielectrophoretic force attainable in the axial direction with corresponding decreasing plate angle and gap distance. The model also predicts larger field variation …

Bulk-Explosion-Induced Metal Spattering During Laser Processing, Cang Zhao, Qilin Guo, Xuxiao Li, Niranjan Parab, Kamel Fezzaa, Wenda Tan, Lianyi Chen, Tao Sun

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Spattering has been a problem in metal processing involving high-power lasers, like laser welding, machining, and recently, additive manufacturing. Limited by the capabilities of in situ diagnostic techniques, typically imaging with visible light or laboratory x-ray sources, a comprehensive understanding of the laser-spattering phenomenon, particularly the extremely fast spatters, has not been achieved yet. Here, using MHz single-pulse synchrotron-x-ray imaging, we probe the spattering behavior of Ti-6Al-4V with micrometer spatial resolution and subnanosecond temporal resolution. Combining direct experimental observations, quantitative image analysis, as well as numerical simulations, our study unravels a novel mechanism of laser spattering: The bulk explosion of …

A Hybrid Process Integrating Reverse Engineering, Pre-Repair Processing, Additive Manufacturing, And Material Testing For Component Remanufacturing, Xinchang Zhang, Wenyuan Cui, Wei Li, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metallic components can gain defects such as dents, cracks, wear, heat checks, deformation, etc., that need to be repaired before reinserting into service for extending the lifespan of these parts. In this study, a hybrid process was developed to integrate reverse engineering, pre-repair processing, additive manufacturing, and material testing for the purpose of part remanufacturing. Worn components with varied defects were scanned using a 3D scanner to recreate the three-dimensional models. Pre-repair processing methods which include pre-repair machining and heat-treatment were introduced. Strategies for pre-repair machining of defects including surface impact damage, surface superficial damage and cracking were presented. Pre-repair …

Transient Analysis Of Diffusion-Induced Deformation In A Viscoelastic Electrode, Yaohong Suo, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

In this study, we analyze the transient diffuse-induced-deformation of an electrode consisting of the conducting polymer polypyrrole (PPY) by using the theories of linear viscoelasticity and diffusion-induced stress. We consider two constitutive relationships with dependence of viscosity on strain rate: Kelvin-Voigt model and three-parameter solid model. A numerical method is used to solve the problem of one-dimensional, transient diffusion-induced-deformation under potentiostatic operation. The numerical results reveal that the maximum displacement occurs at the free surface and the maximum stress occurs at the fixed end. The inertia term causes the stress to increase at the onset of lithiation. The stress decreases …

Cooking Hand Multi-Tool, Amanda D. Meares, Amy H. Wilson, Ethan G. Littlejohn, Duania A. Evans

Biomedical Engineering

The purpose of this project was to devise a solution for Jorge Segura, a US Marine who was wounded in Afghanistan and had to have his non-dominant arm amputated above the elbow. His current prosthetic attachments are not suited to cooking tasks, so he needed a way to cook more effectively with either prosthetic attachments or accessibility devices. The main tasks that he needed help with was holding down food on cutting boards and stabilizing pots, pans, and bowls especially when stirring. After background research, exploring commercially available devices, and talking with our challenger, our solution was to design three …

Additive Manufacturing Powder Removal: Viper 2.0, Andrew D. Epperson, Sean Mccracken, Melissa O'Neil, Alex Ward

Mechanical Engineering

This report presents the final design review of this senior project team. The project is being sponsored by Lawrence Livermore National Laboratory, a federal design agency. Lawrence Livermore National Laboratory is interested in improving their metal additive manufacturing process. The goal of this senior project is to improve the efficiency and safety of a method currently being used to remove metal powders for additively manufactured components. A senior project team in 2017-2018 created the Vibration Induced Powder Evacuator and Reclaimer (VIPER), a device that uses a vibration motor to shake a printed part until it is clean from excess powder. …

Cal Poly Satellite Positioning Systems: "Thrust Or Bust!", Josh W. Neiman, Milena A. Milich, Gerardo Ramirez, Joshua A. Tran

Mechanical Engineering

Satellites need a way to make precise corrections to their orbit and positioning. The purpose of this project is to design a gimbal mechanism for Astranis that orients an ion thruster along a requested vector. The gimbal must produce any vector within a 2.5° cone in a thirty-minute window. Current systems are expensive and not well suited to this application. The design must be operable in a space environment and optimize mass, size, and reliability. Our design toggles between four discrete positions to achieve an average thrust vector. The gimbal accomplishes this using four solenoids that tilt a plate about …

C6 Wheels, Samuel L. Pizot, Luke Martin, Josh Warner, Jonah Levis

Mechanical Engineering

This document details the C6 Wheels project being undertaken for senior design. The objective is to design and manufacture carbon fiber reinforced polymer wheels for the Cal Poly Formula Society of Automotive Engineers (FSAE) team. The wheel shells will be used on FSAE’s competition vehicles. FSAE requested the wheels to improve the handling characteristics of their vehicles by reducing the unsprung and rotational mass. They have attempted carbon fiber wheels previously but have not yet run any on their vehicles. FSAE specifically proposed the design of carbon fiber shells with an aluminum center as opposed to full carbon fiber wheels …