Computer-Aided Engineering and Design Commons^™

Multi-Platform Suppressor Design Project, Wyatt A. Openshaw, Alex B. Chiples

Williams Honors College, Honors Research Projects

The Multi-Platform suppressor is a design that is meant to bridge the gap in the suppressor market by being compatible and configurable with both rifle and pistol platform firearms. In the specific design and prototype referenced in this report, the Multi-Platform suppressor was designed to be used with 9mm pistol and 5.56x45mm rifle calibers with safety, effectiveness, and practicality in mind. To achieve this, the suppressor is configurable, utilizing a Nielsen device in the pistol configuration and a solid mount adapter that replaces the Nielson device piston and spring while in the rifle configuration. This allows the suppressor to retain …

Partially Stratified Combustion Of Natural Gas For Spark Ignition Engines, Philip S. Zoldak

Dissertations, Master's Theses and Master's Reports

In this work, the advantages of partially stratified direct injection natural gas versus premixed port-fueled injection natural gas spark ignited engines has been studied. The volumetric efficiency, ratio of specific heats and turbulent kinetic energy was found to be higher with direct injection versus port-fueled injection thus improving thermal efficiency. A background study of optical chamber experimental data was performed to develop an understanding on the effect of pressure ratio on direct injection of methane under both fully-expanded (sub-sonic) and under-expanded (super-sonic) conditions. Under-expanded jets had a noticeable advantage in terms of turbulent kinetic energy, which led to enhanced air …

Cfd And Heat Transfer Analysis Of Rocket Cooling Techniques On An Aerospike Nozzle, Geoffrey Sullivan

College of Graduate Studies: Theses & Dissertations

In recent years the development of rocket engines has been mainly focused on improving the engine cycle and creating new fuels. Rocket nozzle design has not been changed since the late 1960s. Recent needs for reliable and reusable rockets, as well as advancements in additive manufacturing, have brought new interest into the aerospike nozzle concept. This nozzle is a type of altitude adjusting nozzle that is up to 90% more efficient than bell nozzles at low altitudes and spends up to 30% less fuel. Since the nozzle body is submerged in the hot exhaust gasses it is difficult to keep …

Development Of A Thermal Desalination System Using Low Quality Thermal Energy, Takudzwa C. Chipunza

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Development of a Thermal Desalination System Using Low Quality Thermal Energy

Takudzwa Chipunza

The blowdown water from the cooling tower of the power plant and the produced water from shale gas industry cannot be disposed directly to the environment as they may contain dissolved solids that are harmful to the environment. A detailed physical and chemical process to remove the mineral and organic solids has been developed in West Virginia University. Such a process includes running the blowdown and produced water through a softening tank, activated carbon tank, and a reverse osmosis (RO) system. The RO reject contains a …

Deep Learning Strategies For Pool Boiling Heat Flux Prediction Using Image Sequences, Connor Heo

Graduate Theses and Dissertations

The understanding of bubble dynamics during boiling is critical to the design of advanced heater surfaces to improve the boiling heat transfer. The stochastic bubble nucleation, growth, and coalescence processes have made it challenging to obtain mechanistic models that can predict boiling heat flux based on the bubble dynamics. Traditional boiling image analysis relies on the extraction of the dominant physical quantities from the images and is thus limited to the existing knowledge of these quantities. Recently, machine-learning-aided analysis has shown success in boiling crisis detection, heat flux prediction, real-time image analysis, etc., whereas most of the existing studies are …

Optimized Tip Cooling Using Am Process, Alberto H. Gamez, Lourdes Sarmiento Martinez, Andrew Van Bogelen

Mechanical Engineering

This Final Design Review (FDR) reports on the senior design project undertaken by our team of mechanical engineering seniors at California Polytechnic State University, San Luis Obispo. This project seeks to use the additive manufacturing process to improve the existing design of a Taurus 60 gas turbine injector tip. The current injector tip is owned by Solar Turbines, a designer and manufacturer of gas turbines for electric generation, propulsion, as well as natural resource transportation. The challenge at hand is to design a new injector tip that will be reliable for at least 60,000 hours and provide ease of replacement, …

Geometrically Complex Planar Heat Exchangers, Derli Dias Do Amaral Junior, Jose Lage

Mechanical Engineering Research Theses and Dissertations

In this study, geometrically complex planar heat exchangers, designed in line with the Constructal Law and operating at steady-state, are investigated numerically. The work is divided into two parts, one focusing on diffusion heat transfer in a rectangular plane and another on conjugate diffusion-convection heat transfer in a circular plane heat exchanger.

In the first part, a heat generating rectangular solid volume made of a low conductivity material is cooled through a small, isothermal side-section of the domain. The diffusion cooling process is improved by distributing within the heat generating material a fixed amount of a high conductivity material. The …

Marangoni Propulsion Of Active Particles, Saeed Jafari Kang

Dissertations, Master's Theses and Master's Reports

We study the surfing motion of active particles located at a flat liquid-gas interface. The particles create and maintain a surface tension gradient by asymmetrically discharging a surface tension-reducing agent. We employ theory and numerical simulation to investigate the Marangoni propulsion of these active surfers. First, we use the reciprocal theorem to establish a relationship between the propulsion speed and the release of the active chemical. This theoretical relation is utilized to examine the effect of wall confinement and geometry on the Marangoni-driven motion of active particle when the inertial effects are negligible and when the transports of the released …

Entertainment 721, Mark Hendricks, Noah John, Jadon Vanyo, Chelsea Payne

Williams Honors College, Honors Research Projects

The goal of this project was to design a luxury, aesthetically pleasing entertainment system with a TV lift mechanism that could be remote controlled. The design would also include a cooling cabinet for gaming systems, a remote locking system, and additional storage. Using a morphological chart and weighted decision matrix for each subsystem key features were determined to be included in the design. Several performance benchmarks were determined to accomplish the team’s design. Almost every benchmark was successful in the build of the first prototype. Several heat calculations and FEA analyses were performed on the system to ensure the success …

Thermo-Fluid Characterizations Of The Powder-Bed Fusion Additive Manufacturing Processes Using Laser And Electron Beam, M Shafiqur Rahman

LSU New Orleans Theses and Dissertations

The powder-bed fusion (PBF) process is a subdivision of Additive Manufacturing (AM) technology where a heat source at a controlled speed selectively fuses regions of a powder-bed material to form three-dimensional (3-D) parts. Two of the most effective PBF processes are selective laser melting (SLM) and electron beam additive manufacturing (EBAM), which can fabricate full-density metallic parts in a layer-by-layer fashion. In this study, thermal behavior and melt-pool dynamics in the PBF process are investigated by developing 3-D multiphysics-based thermo-fluid models for both SLM and EBAM, containing Ti-6Al-4V alloy as a powder-bed material. The laser and electron beams are modeled …

Molecular Mechanisms And Design Of Hydrogen-Bonded Materials For Thermal Applications, Jinlong He

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heat transfer at the nanoscale plays an important role in determining the reliability and performance of many innovative advanced materials technologies such as nanoelectronics, semiconductor, biomedical devices, polymers, and composites. Extensive efforts have been made to design materials with extraordinary thermal properties. However, fundamental understanding of heat transfer in many of these materials is still not lacking, because the thermal transport processes are governed by several factors including molecular morphology and chemical bonding. Among these factors, the atomic bonding between two dissimilar materials or within single materials is of particular interest due to its ubiquity and importance in physical processes. …

A Computational Study Of Water Mobility On Smooth Surface, Cavities And Porous Structure With Hydrophilic And Hydrophobic Coatings, Kok Wee Yong

Student Works (2020-2029)

This research focus on water mobility and discovers a new phenomenon where droplet accelerates on a hydrophilic cavity surface when sliding down from a hydrophobic surface. The kinetic energy of droplet increases six (6) times higher than before sliding into the first cavity. This finding is useful for creating an effective way of filling liquids into cavities for passive microfluidics related devices. The work consists of validating cases using Computational Fluid Dynamics (CFD) software. The first part of the research reviews the literature regarding CFD modelling of a water droplet (i) sliding down on a surface, (ii) detachment in a …

Heat Transfer Analysis Of A Data Centre, Arumainathan Kabildev

Student Works (2020-2029)

Data centres are an integral part of networking as it houses servers that facilitate incoming and outgoing data flow. A resolute cooling approach is needed to overcome the hot air dissipated by these servers. This research focused on the computational fluid dynamics (CFD) simulation of the heat transfer modelled upon Telekom Malaysia (TM) City’s data centre 3. The simulation was carried out to ascertain the heat distribution across the data centre by using ANSYS Fluent. The results indicated that the server racks’ inlet temperature reaches 29.79 oC, which is close to the maximum permissible limit according to recommendations provided by …

Fly Ash Based Geopolymer For High Temperature And High Compressive Strength Applications In Aggressive Environment, Aaryan Manoj Nair, Akm S. Rahman

Publications and Research

Geopolymers are the results of geosynthetic reactions between aluminosilicates and strong bases. This results in chemical bonds between aluminum (Al), Silicon (Si)and oxygen (O) composing polymer rings in tetrahedral coordination. These bonds give them widespread useful applications such as high heat bearing ceramics, and base construction material whilst being far more environmentally conscious. The purpose of the experiment is to examine the effect of Silicon Carbide whisker and inorganic glass particles on thermal and mechanical properties of Geopolymers. This study will help understand the effect of various compositions and concentrations of SiO₂ in mechanical strength. In this experiment, the …

Dartmouth Formula Racing: Full Electric Battery System Design, Matt Gardner, Jacob Hagler, Ruthie Nordhoff, Otto Salmi

ENGS 89/90 Reports

Dartmouth Formula Racing (DFR) lacked an electrical energy storage system that was Formula Hybrid rules-compliant, optimized for FH events, safe, reliable, and integrated with the rest of their vehicle. Additionally, the team lacked the academic and professional resources required to bring a thorough, analytical approach to the design, testing, and documentation of the new storage system. Our team designed and built a Lithium-Ion battery pack (accumulator) containing energy storage, active cooling, battery management and temperature monitoring systems, and control circuitry compatible with DFR’s vehicle. Collaboration throughout design, fabrication, assembly and testing processes ensured effective knowledge transfer to the DFR team.

Generation Of Premix Laminar Flame Speed Library, Sai Prashanth Kumar

Dissertations, Master's Theses and Master's Reports

The Laminar flame speed is an essential parameter in measuring turbulent premixed combustion applied in Spark ignition engines. Instead of using power-law correlations, which is valid only for particular ranges, the procedure for generating a premixed laminar flame speed library is defined using MTU – Master mechanism for a wide range of charge mixture conditions inside an engine combustion chamber: Temperature (300 – 700 K), Pressure (1 – 70 bar) and reactant mixture composition of equivalence ratio (0.4 – 2.0) Laminar flame speed library is generated for methane. The mechanism's performance was improved by adjusting the pre-exponential factor of the …

Design, Build, And Analysis Of A Compressed Natural Gas Direct Injection Compression Ignition Single Cylinder Research Engine, Tyler Miller

Dissertations, Master's Theses and Master's Reports

Both experimental and simulation efforts have been employed to further advance the design and build of a single cylinder research engine. The engine will aid in advancing technology and understanding the operation of compression-ignition (CI) engines using natural gas within the heavy-duty engine industry. The basis for the engine is a Cummins 15L ISX engine that has been modified, retrofitted, and instrumented to allow for late-cycle direct-injection of high-pressure compressed natural gas. Along with the engine build, a one-dimensional GT-Power simulation model has been created and used to analyze the engine operation and specify components including the engine compression ratio …

Rocket Motor Nozzle, Corey Hillegass

Williams Honors College, Honors Research Projects

For this honors research and senior design project, the authors will research, analyze, and manufacture a rocket motor nozzle for the Akronauts rocket design team. This research and design project will improve how the rocket design team will decide and manufacture nozzles going forward. The impact of this improvement allows the rocket design team to take steps toward being self-sustaining by manufacturing student designed parts as opposed to commercially bought parts. This will not only be successful in increasing student impact on future designs, but also provides a technical challenge for the authors and will present as an impressive feat …

Measured And Modeled Performance Of A Spring Dominant Free Piston Engine Generator, Ramanjaneya Mehar Baba Bade

Graduate Theses, Dissertations, and Problem Reports (ETD)

Free Piston Engine Generators (FPEG) directly convert the reciprocating piston motion into electricity by using a linear alternator. Unlike conventional engines with piston motion restricted by a crankshaft mechanism, the FPEG piston motion is constrained by the energy available in the system. When stiff springs are considered in the design, the FPEG system attains high frequency with high power and efficiency. The main objective of this research was to model stiff spring-assisted FPEG system dynamics and performance accurately, and to apply the modeling results to the development of a 1kW, spark ignited, natural gas fueled, FPEG experimental prototype. The experimental …

Enhanced Heat Transfer Performance By Shape Optimization Of A Non-Axisymmetric Droplet Evaporating On A Heated Micropillar, Haotian Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Abstract

Enhanced Heat Transfer Performance by Shape Optimization of a Non-axisymmetric Droplet Evaporating on a Heated Micropillar

By

Haotian Wu

Department of Mechanical Engineering and Materials Science

Washington University in St. Louis, 2019

Research Advisor: Professor Damena Agonafer

The stacked multilayer 3D IC structure used in next generation high-powered electronics poses great challenges in dissipating their large heat flux, which causes extreme difficulties for traditional cooling technologies. In response, more advanced two-phase liquid cooling technologies, such as droplet evaporation, which utilizes the latent heat of vaporization to remove excessive heat, have been widely investigated. Compared to traditional single-phase cooling techniques, …

Graphs And Cad: Analyzing The Experience Of A Mechanical Engineering Intern, Matthew Des Biens

Celebration of Learning

A reflection on the experiences of a mechanical engineering intern at Bergstrom Inc., this presentation, by Senior Matt Des Biens, will discuss what it was like working for a manufacturing and design company making HVAC units for large customers across the world. The highlights will be on the projects he worked on, the things that he learned, and his views on working for the company as a whole.

Cpu Cooling Pulse Device For Enhanced Heat Transfer, Hannah Farabee, Noémie L. Iñiguez, Hugo Nunez, Wendy Zwanka

Senior Theses

Ice Dragon Cooling is a company which researches thermofluids and heat transfer technologies. The company’s present research focuses on HVAC and computer applications, with an emphasis on nanofluid development. To support Ice Dragon’s mission, the company wants a product that enhances heat transfer efficiency in liquid-cooled CPU systems. The product is to be a pulse device which increases the turbulence of a liquid across a computer CPU cooling block, thereby expediting heat transfer away from the CPU.

The needs for Ice Dragon Cooling were determined based on engineering knowledge and industry consultation. After further analysis, it was determined that increasing …

Composite Recycler: Frame, Alfonso Olivera

All Undergraduate Projects

How can composites be recycled? The Composite Recycler is an ongoing project that started in September 2017. The purpose of this project was to create a machine that will delaminate the composites, cut them, and heat them up to separate the resin from the composites so they can be recycled. A group was put together for the 2018-2019 academic year to further the project as a whole improve the operation of the device. The existing base was used as well as the cutter and the power sources. The upgrades included; a housing to support the transport rollers and changing from …

Large Eddy Simulations Of Vertical Jets In Crossflow, Pranaya Pokharel

LSU Doctoral Dissertations

Jets in crossflow (JICF) have applications ranging from oil spill to film cooling of turbine blades. Hence, an understanding of the flow physics is important. The majority of the research has been conducted for low velocity ratios between jet and crossflow with round jets. JICF is demonstrated to behave differently for high velocity ratios and different jet shapes. Circular and rectangular jets are commonly used in aircraft applications. Current study focuses on high velocity ratio JICF issuing from both circular and rectangular exit.

For simulating JICF, an in house code “Chem3D” is used with Large Eddy Simulation (LES) to model …

Investigation Of The Performance And Emissions Characteristics Of Dual Fuel Combustion In A Single Cylinder Idi Diesel Engine, Johnnie L. Williams Jr

College of Graduate Studies: Theses & Dissertations

Restrictions in the allowable exhaust gas emissions of diesel engines has become a driving factor in the design, development, and implementation of internal combustion (IC) engines. A dual fuel research engine concept was developed and implemented in an indirect injected engine in order to research combustion characteristics and emissions for non-road applications. The experimental engine was operated at a constant speed and load 2400 rpm and 5.5 bar indicated mean effective pressure (IMEP). n-Butanol was port fuel injected at 10%, 20%, 30%, and 40% by mass fraction with neat ultra-low sulfur diesel (ULSD#2). Peak pressure, maximum pressure rise rates, and …

The Kentucky Re-Entry Universal Payload System (Krups): Sub-Orbital Flights, James Devin Sparks

Theses and Dissertations--Mechanical and Aerospace Engineering

The Kentucky Re-entry Universal Payload System (KRUPS) is an adaptable testbed for atmosphere entry science experiments, with an initial application to thermal protection systems (TPS). Because of the uniqueness of atmospheric entry conditions that ground testing is unable to replicate, scientists principally rely on numerical models for predicting entry conditions. The KRUPS spacecraft, developed at the University of Kentucky, provides an inexpensive means of obtaining validation data to verify and improve these models.

To increase the technology readiness level (TRL) of the spacecraft, two sub-orbital missions were developed. The first mission, KUDOS, launched August 13th, 2017 on a Terrier-Improved Malamute …

Additive Manufacturing For Post-Processing, Nathan D. Goodwin, Andrew Furmidge

Mechanical Engineering

Additive Manufacturing for Post Processing (AMPP) is a team comprised of two Cal Poly Mechanical Engineering students: Nathan Goodwin and Andrew Furmidge. The project is focused in the area of metal additive manufacturing (AM) machines, which are still a developing technology. Improvements have been made to the quality of the machines in the past years, but many limitations still exist. One of these is the inability to print parts that are larger than the build volume. In an effort to solve this problem, whole parts are divided into pieces that are printed individually. This team’s senior project is to create …

Refurbished And 3d Modeled Thermal Vacuum Chamber, Lauren M. Glenn

Master's Theses

Spacecraft testing includes acoustics, vibrations, and thermal vacuum. Cal Poly’s Space Environments Lab is equipped with multiple vacuum chambers, but no thermal vacuum chamber. The purpose of this thesis is to incorporate an ATS Chiller system with the HVEC vacuum chamber so students are able to experiment with a thermal vacuum chamber. The ATS Chiller had leaky pipes that needed to be refurbished and a shroud was implemented to improve thermal capabilities of the system. The full system was able to reach temperatures as low as -38ºC and as high as 58ºC at a pressure of 10-6 Torr. The ATS …

Turbulent Transition Simulation And Particulate Capture Modeling With An Incompressible Lattice Boltzmann Method, John R. Murdock

Dissertations, Master's Theses and Master's Reports

Derivation of an unambiguous incompressible form of the lattice Boltzmann equation is pursued in this dissertation. Further, parallelized implementation in developing application areas is researched. In order to achieve a unique incompressible form which clarifies the algorithm implementation, appropriate ansatzes are utilized. Through the Chapman-Enskog expansion, the exact incompressible Navier-Stokes equations are recovered. In initial studies, fundamental 2D and 3D canonical simulations are used to evaluate the validity and application, and test the required boundary condition modifications. Several unique advantages over the standard equation and alternative forms found in literature are found, including faster convergence, greater stability, and higher fidelity …

Micro Debris Generator, Gordan Bradaric, Ross Byers, Stephen Quanci

Mechanical Engineering

This senior project team at Cal Poly consisting of Stephen Quanci, Gordan Bradaric, and Ross Byers has been commissioned by Erik Brown of Lawrence Livermore National Labs to create a way to reliably and consistently entrain microscopic particles into the hot HTTU flow. These particles will be used to compare the loading rates of new HEPA filters by measuring the pressure drop across the filter. The generated particles would simulate typical conditions in which these HEPA filters are expected to operate, namely fine ash. The particles used for loading the filter are intended to simulate the particulate reaching the LLNL …