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Heat Transfer Vest, Nicholas Forsgaard 2018 Central Washington University

Heat Transfer Vest, Nicholas Forsgaard

All Undergraduate Projects

The purpose of this report is to document the progression of the authors senior project. . The of that project was the research of Liquid Cooled Garment (LCG) technology, the generation of a novel LCG prototype and the testing of that prototype relative to a commercial benchmark. As such, this report is a complete narrative of the of these tasks, their execution and the underlying assumptions and commentary. The motivation for this report is to satisfy the capstone requirements of the MET program at CWU by documenting the Senior Project and its subordinate tasks. First, the student designed a LCG system ...


Burning Surface Temperature Measurements Of Propellants And Explosives Using Phosphor Thermography, Ethan A. Whitaker, Alex D. Casey, Steven F. Son 2017 Purdue University

Burning Surface Temperature Measurements Of Propellants And Explosives Using Phosphor Thermography, Ethan A. Whitaker, Alex D. Casey, Steven F. Son

The Summer Undergraduate Research Fellowship (SURF) Symposium

Temperature measurements of propellants and explosives are necessary to create accurate models which lead to better understanding of energetic characteristics such as burning rate. Previous attempts at measuring surface temperatures of burning propellants and explosives using thermocouples have suffered from large uncertainty. Thermographic phosphor thermography employs ceramic powders called phosphors whose spectroscopic properties can be used to remotely and nearly non-intrusively measure temperature. Improved methods were developed for application of this technique to energetic materials to yield more accurate, two-dimensional temperature measurements. In this study, zinc oxide doped with gallium, a thermographic phosphor, was mixed into HMX and RDX powder ...


Spectral Phonon Relaxation Time Calculation Tool Based On Molecular Dynamics, Divya Chalise, Tianli Feng, Xiulin Ruan 2017 University of Texas at Arlington

Spectral Phonon Relaxation Time Calculation Tool Based On Molecular Dynamics, Divya Chalise, Tianli Feng, Xiulin Ruan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermal conductivity is an important material property which affects the performance of a wide range of devices from thermoelectrics to nanoelectronics. Information about phonon vibration modes and phonon relaxation time gives significant insight into understanding and engineering material’s thermal conductivity. Although different theoretical models have been developed for studying phonon modes and relaxation time, extensive knowledge of lattice dynamics and molecular dynamics is required to compute phonon modal frequencies and relaxation times. Therefore, a computational tool which can take simple inputs to calculate phonon mode frequencies and relaxation time will be beneficial. Through this research work, such computational tool ...


Numerical Simulations Of Transcritical Natural Convection, Ruiwen Wei, Carlo Scalo, Mario Tindaro Migliorino, Kukjin Kim, Jean-Pierre Hickey 2017 Purdue University

Numerical Simulations Of Transcritical Natural Convection, Ruiwen Wei, Carlo Scalo, Mario Tindaro Migliorino, Kukjin Kim, Jean-Pierre Hickey

The Summer Undergraduate Research Fellowship (SURF) Symposium

In modern engineering applications, system overheating is a key issue that needs to be solved with efficient and reliable cooling technologies. Among the possible mechanisms that these are based on, natural convection cooling is one of the most frequently employed, with applications ranging from cooling of computer micro-components to large nuclear reactors. While many studies have been performed on natural convection employing supercritical or subcritical fluids, little attention has been given to fluids in their transcritical regime. The latter has the potential to yield high performances while avoiding detrimental effects of two-phase systems (e.g. cavitation). In the present study ...


Modal Phonon Transport Across Interfaces By Non-Equilibrium Molecular Dynamics Simulation, Yang Zhong, Tianli Feng, Xiulin Ruan 2017 Purdue University

Modal Phonon Transport Across Interfaces By Non-Equilibrium Molecular Dynamics Simulation, Yang Zhong, Tianli Feng, Xiulin Ruan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Phonons represent the quantization of lattice vibration, responsible for heat transfer in semiconductors and dielectrics. Phonon heat conduction across interfaces is crucially important for the thermal management of real-life devices such as smartphones, electric vehicles, and satellites. Although recent studies have broadly investigated spectral phonon contribution to lattice thermal conductivity, the mechanism of phonon modal transport across interfaces is still not well-understood. Previous models, including the acoustic mismatch model (AMM) and diffuse mismatch model (DMM), only consider elastic process while neglecting inelastic phonon contributions. Herein, we employ spectral Non-Equilibrium Molecular Dynamics Simulation (NEMD) to probe the temperature and heat flux ...


Us Patent 9,702,573: Nested Heat Transfer System, Sanza Kazadi 2017 Selected Works

Us Patent 9,702,573: Nested Heat Transfer System, Sanza Kazadi

Sanza Kazadi

A novel nested heat transfer system comprises a plurality of chained enhanced entrochemical cells with nested structures. Each enhanced entrochemical cell includes a first chamber containing desiccant, or a higher concentration solution, and a second chamber containing refrigerant,   or   a   lower   concentration   solution.   Preferably,   the   first   chamber   and   the   second   chamber   are   connected   by   a   conduit.  Furthermore,   a   smaller   chamber   in   an   enhanced   entrochemical   cell   is   encapsulated   by   a   larger   chamber   in   an   adjacent   enhanced entrochemical cell, thus forming a nested structure between the two enhanced entrochemical cells. A chain of enhanced entrochemical cells with a plurality of such nested ...


A Wood-Powered Lawn Mower: Separating The Rules Of Thumb From Engineering Design, William White 2017 Western Kentucky University

A Wood-Powered Lawn Mower: Separating The Rules Of Thumb From Engineering Design, William White

Honors College Capstone Experience/Thesis Projects

Biomass gasification, the thermal process of exracting combustible gasses from organic matter, is an established procedure that has been used for many years to provide fuel in various applications. It is a potential source of renewable fuel and has proven useful as a crisis energy source. This thesis investigates the primary engineering science principles involved in gasifier-engine system design. It arises from and supplements a WKU mechanical engineering senior project. The senior project has developed a wood gasification system designed to power a riding lawn mower. The thesis reiews theory-based design and separates it from informal hit and miss approaches ...


Simple Tester For Measuring Lateral Thermal Diffusivities In Composites, Stephen D. Holland, Elizabeth Gregory, Daniel Romero 2017 Iowa State University

Simple Tester For Measuring Lateral Thermal Diffusivities In Composites, Stephen D. Holland, Elizabeth Gregory, Daniel Romero

Stephen D. Holland

Model-based analysis and inversion of thermography data relies on knowledge of thermal diffusivities. Through-thickness diffusivity is readily measured using the flash method [1]. In composite materials, lateral diffusivities may be drastically different from the through-thickness values, but there is no comparable simple and standard approach for measuring those lateral thermal diffusivities. Welch, Heath, and Winfree [2] proposed a technique based on laser line pulse excitation, but that approach requires a reasonably powerful laser and thermal camera with the concomitant costs and safety requirements. In this presentation, we show a simple and low cost (but not entirely nondestructive) system and method ...


Model-Based Inversion For Flash Thermography, Stephen D. Holland, Brian Schiefelbein 2017 Iowa State University

Model-Based Inversion For Flash Thermography, Stephen D. Holland, Brian Schiefelbein

Stephen D. Holland

The thermal image sequences from thermography experiments are blurred by lateral diffusion and therefore hard to interpret. The widely used one-dimensional heat flow model provides a robust interpretation of thickness or delamination from “break time” where lateral diffusion is significant, but is less effective otherwise. As a result, it remains quite common to interpret defects by contrast from the surrounding “acreage” rather than by the intrinsic properties of the defect signal itself.

In this paper, we present an approach for model-based inversion of flash thermography image sequences that attempts to approximately reconstruct the flow or back-surface geometry from the thermal ...


Adhesion Hysteresis And Its Role In Vibrothermography Crack Heating, Bryan E. Schiefelbein, Tyler Lesthaeghe, Ashraf F. Bastawros, Stephen D. Holland 2017 Iowa State University

Adhesion Hysteresis And Its Role In Vibrothermography Crack Heating, Bryan E. Schiefelbein, Tyler Lesthaeghe, Ashraf F. Bastawros, Stephen D. Holland

Stephen D. Holland

Vibrothermography is an NDE inspection which uses vibration to stimulate surface cracks and measure the resultant heat generation. For years, the accepted assumption has been that heat generation in Vibrothermography NDE is due to friction between opposing crack surfaces [1–3]. A frictional mechanism suggests that crack surfaces in sliding shear would generate heat, whereas crack surfaces coming into and out of contact in an opening-closing mode would not, or would generate much less. But cracks heat easily in opening/closing mode and experimental evidence [4] is not consistent with the prediction that heat generation for shear vibration should be ...


Inspection And Model Based Inversion Of Highly Curved Composite Surfaces With Flash Thermography, Bryan E. Schiefelbein, Stephen D. Holland 2017 Iowa State University

Inspection And Model Based Inversion Of Highly Curved Composite Surfaces With Flash Thermography, Bryan E. Schiefelbein, Stephen D. Holland

Stephen D. Holland

With the development of advanced aircraft structures and stringent mechanical requirements, robust and reliable inspection methods are needed to ensure safe operation and maximum utilization of the equipment [1]. Aircraft composite parts can exhibit complex geometries and tight curvature, such as leading edges and chines. These curved structures are difficult to inspect for defects, especially where the local curvature is high [2–4]. Pulsed thermography has the potential for rapid inspection of large areas, making it attractive for depot or field inspection of large aircraft parts. When imaging areas of high curvature, there are a number of confounding factors, including ...


Turbulent Combustion Of Polydisperse Evaporating Sprays With Droplet Crossing: Eulerian Modeling And Validation In The Infinite Knudsen Limit, S. de Chaisemartin, L. Freret, D. Kah, F. Laurent, Rodney O. Fox, J. Reveillon, M. Massot 2017 Ecole Centrale Paris

Turbulent Combustion Of Polydisperse Evaporating Sprays With Droplet Crossing: Eulerian Modeling And Validation In The Infinite Knudsen Limit, S. De Chaisemartin, L. Freret, D. Kah, F. Laurent, Rodney O. Fox, J. Reveillon, M. Massot

Rodney O. Fox

The accurate simulation of the dynamics of polydisperse evaporating sprays in unsteady gaseous flows with large-scale vortical structures is both a crucial issue for industrial applications and a challenge for modeling and scientific computing. The difficulties encountered by the usual Lagrangian approaches make the use of Eulerian models attractive, aiming at a lower cost and an easier coupling with the carrier gaseous phase. Among these models, the multi-fluid model allows for a detailed description of the polydispersity and size-velocity correlations for droplets of various sizes. The purpose of the present study is twofold. First, we extend the multi-fluid model in ...


Conditional-Moment Closure With Differential Diffusion For Soot Evolution In Fire, J. C. Hewson, A. J. Ricks, S. R. Tieszen, A R. Kerstein, Rodney O. Fox 2017 Sandia National Laboratories

Conditional-Moment Closure With Differential Diffusion For Soot Evolution In Fire, J. C. Hewson, A. J. Ricks, S. R. Tieszen, A R. Kerstein, Rodney O. Fox

Rodney O. Fox

The conditional-moment closure (CMC) equation for the evolution of a large Lewis number scalar, soot, is derived starting from the joint probability density function (pdf) equation for the gas-phase mixture fraction, ξ g , and the soot mass fraction, Y s . Unlike previous approaches starting with the joint pdf, the residual terms that result from the typical closure models were retained. A new formulation of the one-dimensional turbulence (ODT) model suitable for spatially evolving flows with buoyant acceleration and radiative transport in participating media was employed to carry out simulations of a prototypical ethene fire. The resulting ODT evolution of ξ ...


Improved Method Of Co2 Laser Cutting Of Aluminum Nitride, Raathai Molian, Pranav Shrotriya, Pal Molian 2017 Iowa State University

Improved Method Of Co2 Laser Cutting Of Aluminum Nitride, Raathai Molian, Pranav Shrotriya, Pal Molian

Pranav Shrotriya

The traditional “evaporation∕melt and blow” mechanism of CO2 laser cutting of aluminum nitride (AlN) chip carriers and heat sinks suffers from energy losses due to its high thermal conductivity, formation of dross, decomposition to aluminum, and uncontrolled thermal cracking. In order to overcome these limitations, a thermochemical method that uses a defocused laser beam to melt a thin layer of AlN surface in oxygen environment was utilized. Subsequent solidification of the melt layer generated shrinkage and thermal gradient stresses that, in turn, created a crack along the middle path of laser beam and caused material separation through unstable crack ...


Jfs Turbine Engine For Cal Poly Mechanical Engineering Department, Dorian Capps, Zoe Kai Tuggle 2017 California Polytechnic State University, San Luis Obispo

Jfs Turbine Engine For Cal Poly Mechanical Engineering Department, Dorian Capps, Zoe Kai Tuggle

Mechanical Engineering

This project concerns the development of a gas turbine engine laboratory activity for use in one of Cal Poly’s technical elective courses in the Mechanical Engineering Department, ME 444: Combustion Engine Design. The class is taught by Dr. Patrick Lemieux, who is also in charge of the on-campus engines lab where the turbine engine will be installed. The engine itself is a JFS-100-13A turboshaft engine that will be coupled to an electric dynamometer inside of the dyno test cell. Students taking the ME 444 class, likely starting in Winter Quarter of 2018, will be able to perform hands-on experiments ...


Additive Manufacturing For Post-Processing, Nathan D. Goodwin, Andrew Furmidge 2017 California Polytechnic State University, San Luis Obispo

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

Mechanical Engineering

No abstract provided.


Mini High Temperature Test Unit Final Design Report, Juan P. Castillo, Kevin Liu 2017 California Polytechnic State University, San Luis Obispo

Mini High Temperature Test Unit Final Design Report, Juan P. Castillo, Kevin Liu

Mechanical Engineering

Lawrence Livermore National Laboratory has invested considerable effort to develop new standard for nuclear grade HEPA filters that can withstand high temperatures along with methods to optimally test not only the experimental filter media, but also new frame seals and media binders. Therefore, LLNL in collaboration with Cal Poly has designed and built a Mini High Temperature Testing Unit (MHTTU) to recreate conditions observed during a fire and to test different materials in an effective, inexpensive, regulated and reliable method. The existing prototype was unable to achieve the ideal testing conditions of 1000°F air at the low flow rates ...


Computational Fluid Dynamics Modeling And Simulations Of Fast Fluidized Bed And Moving Bed Reactors For Chemical Looping Combustion, Mengqiao Yang 2017 Washington University in St. Louis

Computational Fluid Dynamics Modeling And Simulations Of Fast Fluidized Bed And Moving Bed Reactors For Chemical Looping Combustion, Mengqiao Yang

Engineering and Applied Science Theses & Dissertations

Chemical-looping combustion (CLC) is a next generation carbon capture technology with high efficiency and low cost. To assess the potential of this technology for industrial scale power plants, thousands of laboratory scale and many pilot-scale plants have been designed and tested. In recent years, to obtain a thorough understanding of the hydrodynamic behavior inside the reactors and chemical looping combustion process, high-fidelity numerical simulation using Computational Fluid Dynamics(CFD) have been performed. However, CFD simulations in the literature have been limited reported compared to the laboratory scale experiments.

In this thesis, cold flow simulations of a CLC fuel reactor are ...


Computer Simulation Of Pore Migration Due To Temperature Gradients In Nuclear Oxide Fuel, Ian Wayne Vance 2017 University of Arkansas, Fayetteville

Computer Simulation Of Pore Migration Due To Temperature Gradients In Nuclear Oxide Fuel, Ian Wayne Vance

Theses and Dissertations

A phase-field simulation model is being presented that captures the thermal-gradient-driven migration of pores in oxide fuel associated with fuel restructuring. The model utilizes a Cahn-Hilliard equation supplemented with an advection term to describe the vapor transport of fuel material through the pore interior due to gradients in vapor pressure. In addition, the model also captures changes in a migrating pores’ morphology. Simulations demonstrate that the model successfully predicts pore migration towards the hottest portion of the fuel, the centerline. The simulations also demonstrate changes in pore shape that are in agreement with previous experimental observations. Initially isotropic pores are ...


Characterization Of Plastic Deformation Evolution In Single Crystal And Nanocrystalline Cu During Shock By Atomistic Simulations, Mehrdad Mirzaei Sichani 2017 University of Arkansas, Fayetteville

Characterization Of Plastic Deformation Evolution In Single Crystal And Nanocrystalline Cu During Shock By Atomistic Simulations, Mehrdad Mirzaei Sichani

Theses and Dissertations

The objective of this dissertation is to characterize the evolution of plastic deformation mechanisms in single crystal and nanocrystalline Cu models during shock by atomistic simulations. Molecular dynamics (MD) simulations are performed for a range of particle velocities from 0.5 to 1.7 km/s and initial temperatures of 5, 300 and 600 K for single crystal models as well as particle velocities from 1.5 to 3.4 km/s for nanocrystalline models with grain diameters of 6, 11, 16 and 26 nm. For single crystal models, four different shock directions are selected, <100>, <110>, <111> and <321>, and dislocation density behind ...


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