Algorithm Development Of Topology Optimization For Pcm Based Heat Sinks,
2021
University of Arkansas, Fayetteville
Algorithm Development Of Topology Optimization For Pcm Based Heat Sinks, Diego L. De Los Reyes
Mechanical Engineering Undergraduate Honors Theses
With the inherent usage of the computer when dealing with additive manufacturing, it only makes sense to use that higher computing power through simulation and iterative design to use the mathematical concept of topology and optimize the kind of geometry and shapes to be produced for a certain application, especially thermal ones since most 3D printing applications focus on purely the mechanical. To determine what the shape will be, an objective function of how much heat can be dispersed from a hypothetical heat source, assumed to be a type of electronic device, is maximized while being constrained by other variables, …
Transient Performance And Melt Front Characterization Of Phase Change Materials,
2021
University of Arkansas, Fayetteville
Transient Performance And Melt Front Characterization Of Phase Change Materials, Tyler Stamps
Mechanical Engineering Undergraduate Honors Theses
Thermal management systems are often over-designed for average use in order to handle spikes in heat generation, which increases the spatial and financial requirements. One way to mitigate this is via the use of phase change materials (PCMs) as thermal buffers and storage media. This material type exhibits excellent latent heat at the sacrifice of conductivity. The present paper examines the melt front behavior of a common solid to liquid PCM, paraffin, experimentally and numerically. The experimental scenario was a block of PCM with a constant temperature heat flux introduced on one end and a constant temperature cold boundary condition …
Feasibility Study Of Portable Solar Powered Blood Storing Refrigerator,
2021
University of Mississippi
Feasibility Study Of Portable Solar Powered Blood Storing Refrigerator, Saroj Subedi
Honors Theses
This report is focused on the preliminary feasibility of portable solar-powered blood-storing refrigerators primarily based on calculations of energy required to maintain the temperature of the refrigerator, the electricity required throughout the day, calculating sufficiency of power supplied by the solar panel, and selection of battery for power storage. The method and the trend of a feasibility study involve the study of blood properties, separation of blood components after donation, and their storage conditions. Then, the portable size of the refrigeration has been proposed with three different compartments for storage of each blood component. The further methods involve the selection …
Enercon Station Vacuum Pump Replacement,
2021
Kennesaw State University
Enercon Station Vacuum Pump Replacement, Clint Hembree, Jared D'Amico, Connor Moore, Paul Jeffrey Fontenot, Sydnee Castello, J.J. Clements
Senior Design Project For Engineers
This details the progress of the ENERCON pump replacement project as completed by the Kennesaw State University interdisciplinary senior design group. This project is a two-semester capstone effort for the engineering program at Southern Polytechnic School of Engineering, overseen by Dr. McFall during Fall 2020 and Dr. Khalid during Spring 2021 semesters. The 2020-2021 KSU Interdisciplinary Senior Design team was tasked with completing an Engineering Change Package (ECP) for existing vacuum pumps at ENERCON Station. The mechanical, electrical, and civil students worked together, performing evaluations on existing plant systems to ensure the plant could support the new vacuum pumps. By …
Investigation Of Dusting Hole Film Cooling On A Transonic Turbine Blade Tip With A Squealer,
2021
University of Alabama in Huntsville
Investigation Of Dusting Hole Film Cooling On A Transonic Turbine Blade Tip With A Squealer, Matthew Cox
Honors Capstone Projects and Theses
No abstract provided.
Relationship Between Thermal Conductivity And Free Electrons In Metal,
2021
Linfield University
Relationship Between Thermal Conductivity And Free Electrons In Metal, Yansong Liu
Senior Theses
An experiment was designed and conducted to explore the relationship between thermal conductivity with free electrons in metal. In the experiment, copper, iron, aluminum, and titanium rods with close diameters were used to carry out the experiment. Each rod was heated up by a heat unit at one end while cooled on the other end with a heat sink to maintain a steady state. DC current was applied to rods in the direction along, as well as against, the heat flow. Thermal conductivities were measured in these two situations for each rod. Results showed electrons do dominate thermal flow inside …
Experimental Investigation Of The Effects Of Acoustic Waves On Natural Convection Heat Transfer From A Horizontal Cylinder In Air,
2021
California Polytechnic State University, San Luis Obispo
Experimental Investigation Of The Effects Of Acoustic Waves On Natural Convection Heat Transfer From A Horizontal Cylinder In Air, Katherina V. Prodanov
Master's Theses
Heat transfer is a critical part of engineering design, from the cooling of rocket engines to the thermal management of the increasingly dense packaging of electronic circuits. Even for the most fundamental modes of heat transfer, a topic of research is devoted to finding novel ways to improve it. In recent decades, investigators experimented with the idea of exposing systems to acoustic waves with the hope of enhancing thermal transfer at the surface of a body. Ultrasound has been applied with some success to systems undergoing nucleate boiling and in single-phase forced and free convection heat transfer in water. However, …
Thermal Ignition Of A Combustible Over An Inclined Hot Plate,
2021
University of Dhaka
Thermal Ignition Of A Combustible Over An Inclined Hot Plate, Salaika Parvin, Nepal Chandra Roy, Rama S. R. Gorla
Faculty Publications
In this study, the ignition characteristics and the flow properties of the mixed convection flow are presented. Detailed formulations of the forced, natural and mixed convection problems have been discussed. In order to avoid inconvenient switch between the forced and natural convection we introduce a continuous transformation in the mixed convection. We make a comparison between these situations which reveal a good agreement. For mixed convection flow, the ignition distance is explicitly expressed as a function of the Prandtl number, reaction parameter and wall temperature. It has been observed that owing to the increase of the aforesaid parameters, the thermal …
Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment,
2021
University of Kentucky
Numerical Reconstruction Of Spalled Particle Trajectories In An Arc-Jet Environment, Raghava S. C. Davuluri, Sean C. C. Bailey, Kaveh A. Tagavi, Alexandre Martin
Mechanical Engineering Faculty Publications
To evaluate the effects of spallation on ablative material, it is necessary to evaluate the mass loss. To do so, a Lagrangian particle trajectory code is used to reconstruct trajectories that match the experimental data for all kinematic parameters. The results from spallation experiments conducted at the NASA HYMETS facility over a wedge sample were used. A data-driven adaptive methodology was used to adapts the ejection parameters until the numerical trajectory matches the experimental data. The preliminary reconstruction results show that the size of the particles seemed to be correlated with the location of the ejection event. The size of …
Pulse Decay Thermal Conductivity Device,
2021
Central Washington University
Pulse Decay Thermal Conductivity Device, Matthew Schrenk
All Undergraduate Projects
Currently, there are several ways in which thermal conductivity can be calculated or assessed on a given material. However, with each method of testing comes potential limitations such as size, material state, complexity, and time. The goal of this study was to develop a pulse heated thermistor that would reduce all four limitations, thus provide precise and timely results regardless of the material state and size. A thermistor is resistor which changes resistance in accordance to temperature. To achieve the design, heat transfer and electrical methods were applied. As with all resistors, heat is dissipated across the element and released …
Thermal Conductivity Measuring System (Tcoms),
2021
Central Washington University
Thermal Conductivity Measuring System (Tcoms), Lucas Hill
All Undergraduate Projects
The Mechanical Engineering Technology department at Central Washington University is lacking a method to reliably measure the thermal conductivity of bulk materials, with dimensions of at least a 1 cm radius, within a teaching environment. Thermal Conductivity Measuring System (TCoMS) will be a useful tool to perform these measurements as it is able to obtain measurement readings for materials between 0 C and 50 C within 20 seconds. TCoMS will accomplish this by using the pulse decay method of measuring thermal conductivity, a form of transient heat transfer analysis. This method is performed by generating a pulse of heat at …
Jcati Pyrolysis System,
2021
Central Washington University
Jcati Pyrolysis System, Jack Dutton
All Undergraduate Projects
The Joint Center for Aerospace Technology Innovation (JCATI) project is designed to recycle carbon fiber pieces for use in manufacturing. Part of the system requires the removal of resin from the carbon fibers to facilitate the recycling of carbon fiber. To accomplish this task the pyrolysis process is implemented using a commercial grade oven with a conveyor system. Argon gas is injected into the shroud and over the oven to purge the interior of oxygen. The conveyor system enables this to be a batch process. A ramp is used to allow simple addition of material to the conveyor system and …
Hotspot Cooling Performance For Confined Jet Impingement Cooling,
2021
University of Central Florida
Hotspot Cooling Performance For Confined Jet Impingement Cooling, Tanvir Ahmed Chowdhury
Electronic Theses and Dissertations, 2020-2023
The current trend in microelectronics is to manufacture devices with increased computational powers and reduced size. These devices with increased power densities are consequently subject to extreme thermal loads. Thermal management of these power loads is extremely challenging. The presence of the hotspots can make this challenge even more difficult. Jet impingement cooling is one of the top candidates for removing such extreme heat fluxes in microelectronics. Jet impingement cooling can achieve heat transfer coefficients (HTCs) due to its normal incident flow-field and ability to thin the local thermal boundary layer in the stagnation region. This dissertation presents the hotspot …
Effect Of Heat Treatment On Microstructure And Hardness Of A Worn Rail Repaired Using Laser Powder Deposition,
2021
University of Nevada, Las Vegas
Effect Of Heat Treatment On Microstructure And Hardness Of A Worn Rail Repaired Using Laser Powder Deposition, Ershad Mortazavian, Zhiyong Wang, Hualiang Teng
Mechanical Engineering Faculty Research
The frequent replacement of worn rails on tracks brings an immense economic burden on the railroad industry, and also causes significant interruptions to railroad operation. Restoration of worn rails via laser powder deposition (LPD) can considerably reduce the associated maintenance costs. This study was focused on the use of LPD to repair the worn profile of a standard U.S. rail. The microstructure of the 304L stainless steel deposits with a minimum hardness of 85 HRB was composed of austenite, δ-ferrite, and sigma. Micropores were dispersed throughout the deposit, and microcracks were found at the rail-deposition interface. The pearlitic rail substrate …
A Combustion Model For Multi-Component Fuels Based On Relative Reactivity And Molecular Structure,
2021
Michigan Technological University
A Combustion Model For Multi-Component Fuels Based On Relative Reactivity And Molecular Structure, Arash Jamali
Dissertations, Master's Theses and Master's Reports
A reliable multi-component surrogate fuel model needs to be able to represent both physical properties and chemical kinetics of a real fuel. However, enhancing the fidelity of a model with detailed description of physical and chemical behavior of all fuel components found in real fuels is limited by the prohibitive computational load to calculate the combustion chemistry of the fuel. Hence, it is desirable to achieve computational efficiency by reducing the number of chemical surrogates at the minimum expense of prediction accuracy. The objective of this work is to develop a model that can simulate the oxidation of multi-component fuels …
Kinetics Of Elementary Reactions In Graphene Oxidation And Kinetics Of Oh* In Hydrogen Flames,
2021
University of Kentucky
Kinetics Of Elementary Reactions In Graphene Oxidation And Kinetics Of Oh* In Hydrogen Flames, Siamak Mahmoudi
Theses and Dissertations--Mechanical and Aerospace Engineering
Due to diverse applications of graphene, a kinetic mechanism describing rates of elementary reactions is extremely useful. To achieve that goal the elementary reactions need to be detected and their rates need to be determined. In this work the objectives are to use first-principle tools to find those reactions and analyze their paths in the context of graphene oxidation. Density functional theory (DFT) calculations provide the best approximation to the Schr\"{o}dinger equation, which is not feasible to solve analytically for large molecules like graphene. We have performed these calculations to find stable configurations (geometry optimization) and minimum energy paths between …
The Role Of Live Conifer Fuels In Crown Fires Spread,
2021
University of Kentucky
The Role Of Live Conifer Fuels In Crown Fires Spread, Adnan Darwish Ahmad
Theses and Dissertations--Mechanical and Aerospace Engineering
Live foliage for some tree and shrub species can support flaming fire spread at much higher moisture content than dead fuel materials. However, the role of live fuels in forest fires has been controversial in the past decades. Although ignition and spread statistical data for live and dead fuels exist in the literature, a clear understanding of the fundamental difference in the burning behavior is missing. To illuminate the role of live fuel on forest fire spreading, a laboratory ignition experiment was designed to examine the burning behavior of live Norway spruce needles. A schlieren-Infrared combined measurement apparatus was developed …
Evaluation Of Radiative Conductivity Inside A Porous Media With The Effect Of Participating Medium Based On Microscale Imaging,
2021
University of Kentucky
Evaluation Of Radiative Conductivity Inside A Porous Media With The Effect Of Participating Medium Based On Microscale Imaging, Mingping Zheng
Theses and Dissertations--Mechanical and Aerospace Engineering
Space vehicles will experience high loads of heat while entering the planetary atmosphere. At such high temperature, radiation becomes the dominant mode of heat transfer. Since the atmospheric entry environment is nearly impossible to duplicate in a laboratory environment, a numerical model to evaluate thermal performance of the thermal protection system was established. The model simulates the radiative heat transfer process in highly porous media, and the process also takes into account the influence of the participating media. An iterative approach and periodic boundary conditions are used to solve The unbalanced heat flux problem. CT scanned microscale Fiberform and artificial …
Waste Heat Recovery Of Industrial Regenerative Thermal Oxidizer (Rto), A Case Study,
2021
University of Kentucky
Waste Heat Recovery Of Industrial Regenerative Thermal Oxidizer (Rto), A Case Study, James Trimpe Jr.
Theses and Dissertations--Mechanical and Aerospace Engineering
Industrial processes that utilize and release hazardous compounds into the atmosphere are required to break down those compounds before exhausting them from their facilities. An industry-recognized method to break down those hazardous compounds is through thermal oxidation. Thermal oxidation is a process where the compounds are exposed to their auto-ignition temperature in an oxygen-rich environment and combust. The output of thermal oxidation is carbon dioxide, water vapor, and heat. Thermal oxidizers are equipment that performs the thermal oxidation process. The heat output from thermal oxidizers is wasted if directly exhausted into the atmosphere. Regenerative thermal oxidizers (RTOs) use the waste …
Modeling Thin Layers In Material Response Solvers,
2021
University of Kentucky
Modeling Thin Layers In Material Response Solvers, Christen Setters
Theses and Dissertations--Mechanical and Aerospace Engineering
Thermal Protection Systems (TPS) are a necessary component for atmospheric entry. Most TPS contain thin layers of various materials such as ceramic coatings, pore sealers and bonding agents. When modeling TPS, these thin layers are often neglected due to the difference in scale between the TPS (centimeters) and the thin layers (micrometers). In this study, a volume-averaging flux-conservation method is implemented in the governing equations of a finite volume material response code. The model proposes the addition of a volume and area fraction coefficient which utilizes a weighted-averaging between the amount of thin layer and heat shield material in a …
