Mechanical Engineering Commons^™

Thermal Destratification Of Air Streams To Improve The Cooling Provisioning Of Air-Cooled Data Centers, Anto Joseph Barigala Charles Paulraj

Mechanical and Aerospace Engineering Theses - Archive

Air side economization is an arrangement of duct, damper and automatic control system which together allow introducing outside air to reduce the mechanical cooling during mild or cold weather thereby decrease the energy consumption. The outside ambient air and heated return air from the information technology (IT) pod is mixed inside a dedicated space to achieve a target cold aisle operating temperature and thereby increase economization. Major constrain faced by the design engineers while designing the Mixing Chamber/ Plenum is the stratification of air stream due to the Temperature gradient in the mixed air stream and this stratification can be …

Development Of A One-Equation Turbulence Model Based On K-Ε Closure And Its Extension For Computing Transitional Flows By Including An Intermittency Transport Equation, Cheng Peng

McKelvey School of Engineering Graduate Student Theses & Dissertations

No abstract provided.

Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites, Kirby Simon

McKelvey School of Engineering Graduate Student Theses & Dissertations

Carbon fiber reinforced thermoplastic (CFRTP) composites are becoming increasingly attractive materials in manufacturing due to their lightweight nature, mechanical strength, and corrosion resistance. Surface activation of these materials is usually required during processing to increase the bond strength of assemblies (aerospace and automotive industries) or improve adhesion with implants (biomedical industry). Industrially-relevant, nondestructive quality control methods for assessing the activation state of these materials do not currently exist, however. Applying principles discovered through the use of scanning probe microscopy, a multiple-probe Kelvin scanning (MPKS) device has been developed that can assess the uniformity of the activation state of plasma-treated CFRTP …

A Comparison Of Discrete Damage Modeling Methods: The Effect Of Stacking Sequence On Progressive Failure Of The Skin Laminate In A Composite Pi-Joint Subject To Pull-Off Load, Joseph Keith Novak

Mechanical and Aerospace Engineering Theses - Archive

Discrete damage modeling of composite failure mechanisms including delamination, matrix cracking, and their interactions was performed for the skin laminate in a composite pi-joint test specimen subject to a pull-off load. The skin laminate stacking sequence was varied, and the pull-off load and path of predicted damage were recorded. Within the study two discrete damage modeling tools were used, Abaqus XFEM with a LaRC05 built-in user subroutine and BSAM. Both tools implement failure criteria developed at the NASA Langley Research Center (LaRC) to predict the location of damage initiation and both tools use similar cohesive zone models to model damage …

Duocel Metal Foam Display Cases, Kate Goldsworthy, Katherina Prodanov, Benjamin Swanson, Syed Hasan

Mechanical Engineering

This Final Design Review (FDR) report outlines the senior design project that was conducted by a team of four mechanical engineering students at California Polytechnic State University-San Luis Obispo for ERG Materials and Aerospace Corporation. The goal of this project was to design displays that showcase the properties of ERG’s Duocel® foam at tradeshows and client meetings. To better understand the needs of our sponsor, the team researched Duocel®’s capabilities, related technologies, and relevant standards and regulations. With this information, we further defined the problem by creating a problem statement and a set of engineering specifications through a Quality Function …

Insulated Solar Electric Cooker With Phase Change Thermal Storage Medium, Justin Brett Unger, Nathan Robert Christler, Matthew Weeman, Marcus Edward Strutz

Mechanical Engineering

This final design review document outlines the senior design project carried out by a team of four mechanical engineering students at the California Polytechnic State University – San Luis Obispo under the sponsorship of Dr. Peter Schwartz of the Cal Poly Physics department. The aim of this project was to improve upon the design of previously developed Insulated Solar Electric Cookers (ISECs) by adding a thermal storage system to allow for quicker cook times and the ability to cook food at non-peak solar hours. The team’s goal was to develop a working prototype utilizing a phase change medium as the …

Framed Human Powered Vehicle Frame, Keyanna Brielle Henderson, Brendon Howard Morey, Kyra Noelle Schmidt, Austin Patrick Henry

Mechanical Engineering

The following is the Final Design Review (FDR) Report for Framed, a team tasked with designing and fabricating the frame of the 2018-2019 Cal Poly Human Powered Vehicle (HPV) Club bike. The bike is to be raced at the 2019 World Human Powered Speed Challenge in Battle Mountain, Nevada with the goal of breaking the American collegiate speed record. The purpose of the FDR Report is to introduce the project’s background and objectives, discuss the final design, and present the results of manufacturing and testing. Prior to beginning work on the design of the frame, the group conducted extensive research …

Vaccine Cooler For The Global Poor, Benjamin J. Larson, Cooper E. Gibson, Eilbron Younan, Cody R. Volk

Mechanical Engineering

Cal Poly physics professors Peter Schwartz and Nathan Heston approached the Solar Freeze team with the problem that remote communities in Africa have limited access to modern-day medicine or vaccines. They suggested that we try and design a cooling device that can keep vaccines cold for multiple days at a time while the medicine is transported to remote villages. Currently, there are vaccine cooler products on the market, but most of them are very expensive or lack portability. Peter and Nate have tasked the Solar Freeze team to come up with a less expensive solution that is also portable and …

Solar Tracking Using A Parallel Manipulator Mechanism To Achieve Two-Axis Position Tracking, Joseph Otto Hubach

Graduate Theses - Mechanical Engineering

A novel solar tracker is presented that uses a parallel manipulator for the tracking mechanism instead of a traditional serial manipulator. The motivation is to create a solar tracker that displays the advantages of two-axis tracking systems (e.g., increased exposure to incident radiation, and enabling the use of efficient concentrating solar cells) while addressing some of the disadvantages of current two-axis tracking systems (e.g., the difficulties associated with having actuators mounted to moving elements within the mechanism). The mobility of the proposed parallel manipulator is examined using Grübler’s Criterion to establish that the manipulator displays the required two degrees of …

Silicone Tadpole: Research Into Soft Bodies, Danielle Fernandez

Mechanical Engineering Undergraduate Honors Theses

In this thesis, research is conducted in the area of soft robotics by building a soft tadpole that can deform with a specific air pressure. The goal is to mimic the motion of an organic tadpole in respect to its S-shaped tail movement. The angle of deformation, derived from material mechanic theories, ranges from 45 to 80 degrees for this type of movement. The design includes a head compartment which acts as a tank to transfer nitrogen pressure and a tail section that receives the said pressure and bends as a result. The tail section was designed with two rows …

Micromechanics-Enriched Finite Element Modeling Of Composites With Manufacturing Or Service-Induced Defects, Alden S. Hyde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Composite materials are increasingly used in many industries due to the high strength and low weight properties that they exhibit. Since composites are becoming more popular, they are being used in applications such as aircraft, boats, wind turbine blades, and even sports equipment. Composite behavior is complicated since they are made up of two completely different materials such as strong thin fibers and a relatively weaker resin material that hold the fibers together. It is becoming more important to understand how composites behave in different situations so that equipment designers have reliable material information in order to design safe products …

Mechanical Characterization And Fracture Behavior Of Magnesium Zk60a Alloy (Uns M16600), Mohamed Kamal I. H. Temraz

Theses

This research work focuses on studying the mechanical and fracture behavior of one of magnesium ZK60A (UNS M16600) extrusion. The material has many industrial applications and its characteristic should be measured for proper component or system design. Several tests were conducted following the standard procedures to determine the mechanical characteristics of the material. In addition, the fracture toughness of the material has been measured using the fracture toughness-thickness curve. A stress intensity factor K was used as a fracture parameter to determine the plane strain fracture toughness KIC of ZK60A magnesium alloy using a single edge notch bend (SENB) specimen …

Analysis And Proposed Improvement Of Hamilton County Vw Elab Equipment, Hiroshi Yanagida

Honors Theses

Digital fabrication laboratories have revolutionized project based learning within K-12 STEAM education curriculum. However, classroom utilization of the labs often requires excessive machine hours to accomplish, and this often leads to rapid machine depreciation and disrepair. Many educators do not have the time to repair their equipment while developing curriculum and engaging with their students. This study focuses on building a repair history for common digital fabrication equipment, which includes Prusa i3 Mk2S FDM 3D printers, laser cutters, and CNC routers. Data were collected over a 6 month period to find which machines encountered the most issues. The 3D printers …

Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper presents a systematic method to analyse the stability of systems with single delay in which the coefficient polynomials of the characteristic equation depend on the delay. Such systems often arise in, for example, life science and engineering systems. A method to analyze such systems was presented by Beretta and Kuang in a 2002 paper, but with some very restrictive assumptions. This work extends their results to the general case with the exception of some degenerate cases. It is found that a much richer behavior is possible when the restrictive assumptions are removed. The interval of interest for the …

Impact Of Immersion Cooling On Thermo-Mechanical Properties Of Pcb's And Reliability Of Electronic Packages, Shrinath Shrinivas Ramdas

Mechanical and Aerospace Engineering Theses - Archive

Immersion cooling technique is used for the thermal management of high-density data centers to avoid overheating of components and failure of servers. However, to use this as a viable cooling technique, the effect of dielectric coolants on the reliability of server components needs to be evaluated. Previous work reported contradicting findings for Young’s modulus of PCBs, providing motivation for this work. This study focuses on effect of immersion cooling on the thermos-mechanical properties of printed circuit board (PCB) and its impact on reliability of electronic packages. Changes in thermo-mechanical properties like Young’s modulus (E), Glass transition temperature (Tg), Coefficient of …

Development Of A Single Sensor Approach For Capturing Three-Dimensional, Time Resolved Flame And Velocity Information, Jonathan Reyes

Electronic Theses and Dissertations

Performing non-intrusive measurements is the key to acquiring accurate information representative of what is being observed. The act of measuring often changes the environment being observed altering the information that is being obtained. Due to this, the community of fluid scientists have gravitated towards using laser-based measurements to observe the phenomena occurring in their experiments. The study of fluids has advanced since this point, utilizing techniques such as planar laser induced florescence (PLIF), particle image velocimetry (PIV), laser doppler velocimetry (LDV), particle doppler anemometry (PDA), etc. to acquire chemical species information and velocity information. These techniques, though, are inherently two-dimensional …

Decentralized Consensus-Based Control Allocation For Some Dynamical Systems, August Mark

Electronic Theses and Dissertations

In this dissertation, three separate studies, wherein techniques from graph theory and consensus control are used to address control allocation problems, are presented. In the first study, a decentralized allocator is presented for synthetic jet actuators and control surfaces onboard a small unmanned aerial vehicle to cooperatively generate desired aerodynamic moments. First order linear dynamics are assumed for both the synthetic jet actuators and control surfaces. A weighted consensus algorithm with limited feedback is used for the aerodynamic moment contribution allocator considering constraints. In the second study, the same allocation problem as in the first study is considered, but the …

How Infant Positioning Impacts Hip Motion And The Associated Implications For Babies With Hip Dysplasia, Lauren Buchele

Biomedical Engineering Undergraduate Honors Theses

Developmental dysplasia of the hip (DDH) refers to a group of disorders, ranging from slight instability (Grades 1-3) to a severe dislocation (Grade 4) of the femoral head from the acetabulum [1]. In order to treat DDH in infants, a reduction procedure and the use of a lower body harness to secure the hip joint as the bones and ligaments re-form properly is typically prescribed. The Pavlik Harness is currently the “gold-standard” orthopedic device used to place hips in proper positioning. However, little research has been reported on the biomechanical affects during use of these device types.

Although the Pavlik …

Mechanical Properties Of Brittle Ceramics: Case Study Of Boron Rich Ceramics And Acropora Cervicornis Coral Skeleton, Alejandro Carrasco-Pena

Electronic Theses and Dissertations

Ceramics are ubiquitous in man-made and natural structures. Their mechanical properties highly depend on their composition, microstructure and level of defects in the bulk of the material, the latter affecting the integrity of the components; such is the case of boron-rich ceramics where large agglomerates create high stressed regions, or coral skeleton where porosity determines their strength against hydrodynamic forces present in the ocean tides. Therefore, studying the properties of ceramic materials using invasive and non-invasive methods helps in the understanding of the link between the properties and the performance of the structures. The aim of this research was to …

Variable Fluid Flow Regimes Alter Endothelial Adherens Junctions And Tight Junctions, Dilshan Ranadewa

Electronic Theses and Dissertations

Variable blood flow regimes influence a range of cellular properties ranging from cell orientation, shape, and permeability: all of which are dependent on endothelial cell-cell junctions. In fact, cell-cell junctions have shown to be an integral part of vascular homeostasis through the endothelium by allowing intercellular signaling and passage control through tight junctions (TJs), adherens junctions (AJs), and gap junctions (GJs). It was our objective to determine the structural response of both AJs and TJs under steady and oscillatory flow. Human brain microvascular endothelial cells (HBMECs) were cultured in a parallel plate flow chamber and exposed to separate trails of …

Dynamic Behavior And Performance Of Different Types Of Multi-Effect Desalination Plants, Mohamed Abdelkareem

Electronic Theses and Dissertations

Water and energy are two of the most vital resources for the socio-economic development and sustenance of humanity on earth. Desalination of seawater has been practiced for some decades and is a well-established means of water supply. However, this process consumes large amounts of energy and the global energy supply is also faced with some challenges. In this research, multi-effect desalination (MED) has been selected due to lower cost, lower operating temperature and efficient in terms of primary energy and electricity consumption compared to other thermal desalination systems. The motivation for this research is to address thermo-economics and dynamic behavior …

Autonomous Vehicles Operating Collaboratively To Avoid Debris And Obstructions, Toan T. Le, Cole W. Oppenheim, James H. Gildart, Kyle M. Bybee

Mechanical Engineering

The purpose of this project is to demonstrate the safety and increased fuel efficiency of an automated collision avoidance system in collaborative vehicle platooning. This project was cosponsored by Daimler Trucks North America headquartered in Portland, Oregon, as well as Dr. Birdsong, and Dr. DeBruhl of Cal Poly. The mechanical engineering team consists of Cole Oppenheim, James Gildart, Toan Le, and Kyle Bybee who worked in coordination with a team of computer engineers. Vehicle platooning is a driving technique to increase the fuel efficiency of a group of vehicles by following a lead vehicle closely to reduce the drag experienced …

Adjustable Seating Systems, Grace Timken, Zachary Dworaczyk, Jasper Lewin, Eric Voss

Mechanical Engineering

The Adjustable Seating Systems team designed and prototyped a collapsible and nestable seat for use in transit vehicles to create more free space for more passengers and cargo. Our team is the second senior project group to have worked at solving this problem. The previous team established a unique seat folding method that is currently pending patent approval. Our team’s responsibility was to improve the ease of use and overall hardware design of the entire seating system. This document captures the efforts that our team has performed to organize an approach to completing a full design and working prototype this …

Danny’S Recumbent Bike Accessibility Device Final Design Report, Joseph J. Lee, Huy Nguyen, Jack Mcatee, John Kulick

Mechanical Engineering

The purpose of this document is to fully define our design solution and explain our manufacturing and testing results. Our project’s goal is to find a way to allow Danny Knutson, a retired Navy pilot and incomplete quadriplegic with limited use of his arms and an impaired sense of balance, to enter and exit his recumbent tricycle without any discomfort for him or his aide. We completed multiple interviews with Danny, patent research, existing product research, and other technical literature research in order to fully understand the problem. We synthesized this information to create a concrete list of customer wants …

High Strollers, Braeden Hammond, Morley Perrin, Reid Bartels, Juan Rodriguez

Mechanical Engineering

This report documents the final product of Jonathon’s new lightweight stroller. The Mechanical Engineering team from Cal Poly, High Strollers, began the project to create a lightweight stroller for the project sponsor, Nina Aguayo, and her son, Jonathon Aguayo, in Fall of 2018. Jonathon is diagnosed with Delayed Brain Development and Hypotonia with some characteristics of Cerebral Palsy. He has a 50lb high intensity stroller to go to and from school. Mrs. Aguayo needed a stroller that is easier to transport while still meeting all of Jonathon’s needs. The re-designed stroller will make leisurely outings for Mrs. Aguayo and Jonathon …

Go With The Flow, Scott Weinhardt, Priscilla Ng, Ben Rydberg, Ritika Makhijani

Mechanical Engineering

This Final Design Review (FDR) report outlines the Fuel System Flow Analysis senior project completed by the presenters listed. Included is research about Solar Turbines’ needs, and objectives for our project, our design decision process and final design, manufacturing, design verification report, final results, and suggestions moving forward with this experiment. The goal of the project is to identify stable pressure fields throughout the Solar Turbines fuel delivery system. Specifically, the optimal placement for taking measurements downstream of the main and pilot fuel control valves. The data is used to validate the accuracy of computational fluid dynamic (CFD) models that …

Bgaas Alloy Semiconductors For Lasers On Silicon, Joshua Mcarthur

Mechanical Engineering Undergraduate Honors Theses

In the world of semiconductors today, there is a large dissonance between optical devices and electrical application. Due to the limitations of electron transport, photonic integrated circuits are soon-to-be vital in fields like telecommunications and sensing. Right now, these PIC’s are mostly made from indium phosphide. Due to its ubiquitous nature, however, there is a huge push to integrate efficient optics with silicon. It’s cheap, abundant, dope-able, and our electronic infrastructure is based on it. The reason why silicon photonics aren’t already commercialized is because of silicon’s indirect bandgap—it is inefficient with optical applications. The problem with combining direct gap …

Construction Of A Hyperspectral Camera Using Off-The-Shelf Parts And 3d-Printed Parts, Connor Heo

Mechanical Engineering Undergraduate Honors Theses

The Arkansas Center for Space and Planetary Sciences (ACSPS) is working together with the Mechanical Engineering Department to build a modifiable camera with 3D-printed parts and off-the-shelf parts (sourced from Edmund Optics and Amazon). The design is to be readily changeable, primarily with the 3D printed parts, as to accommodate new ideas and functionalities in the future. Ultimately, the camera should be relatively cheap while maintaining functionality for proposed use cases. Earlier versions of the design will be tested extensively and rapidly updated in the ACSPS labs with benchtop testing. This will involve subjects with both visible and infrared emissions, …

Open Source Completely 3-D Printable Centrifuge, Salil S. Sule, Aliaksei Petsiuk, Joshua M. Pearce

Michigan Tech Publications, Part 1

Centrifuges are commonly required devices in medical diagnostics facilities as well as scientific laboratories. Although there are commercial and open source centrifuges, the costs of the former and the required electricity to operate the latter limit accessibility in resource-constrained settings. There is a need for low-cost, human-powered, verified, and reliable lab-scale centrifuges. This study provides the designs for a low-cost 100% 3-D printed centrifuge, which can be fabricated on any low-cost RepRap-class (self-replicating rapid prototyper) fused filament fabrication (FFF)- or fused particle fabrication (FPF)-based 3-D printer. In addition, validation procedures are provided using a web camera and free and open …

The Analysis Of Erlanger Hospital’S Suture Inventory Management Operations, Amanda George

Honors Theses

This paper evaluates the impact of using mechanical engineering and operations management principles to an inventory management system in Erlanger Hospital. Erlanger Hospital is a local, nonprofit hospital system in Chattanooga. Erlanger serves as a tertiary referral hospital and a Level I Trauma Center in the region. Therefore, they are heavily depended on during times of crisis or emergency [2]. This study focuses specifically on reducing the loss and ultimate waste of sutures across Erlanger’s surgery wing. A criteria for the appraisal of using mechanical and manufacturing engineering to improve the current system is established based on existing data regarding …