Mechanical Engineering Commons^™

Biomechanical Investigation Of Elite Place-Kicking, Chase M. Pfeifer

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Many studies aim to understand the fundamentals of kicking commonly displayed by soccer players [4,6,10,16,17,18,24,25,28,29,30,34,36,38,40]. Of those studies, most are limited to a two-dimensional (2D) analysis using high-speed cameras for position tracking or utilizing electromyography to observe the activity of select muscles [4,6,18,25,29,36]. The few studies that investigate kicking using a three-dimensional (3D) model are limited in their position tracking capabilities and focus mainly on joint flexion potentials and foot speed.

This dissertation is a comprehensive biomechanical analysis (kinematic and EMG) of the field-goal place-kicking techniques of four elite kickers in American football. Data were compared and contrasted with ball …

Semi-Annual Program Progress Performance Report For University Transportation Systems, Pppr#4, October 2015, Florida Solar Energy Center, David L. Block

FSEC Energy Research Center®

A summary of the major activities reported in the following pages is as follows. In the research area, the collection and analysis of data from the Nissan funded DC fast charger at FSEC (Project #3), the development of a student and faculty battery laboratory at Tuskegee University (Project #8), the opening of a new University of Hawaii battery test lab (Project #9), a computer model to optimize electrical costs for Tallahassee StarMetro buses (Project #14), and the installation and beginning of data collection from the FSEC wireless charging laboratory (Project #15). Detailed industry interactions for the period included Nissan, NovaCharge, …

Materials For Programmed, Functional Transformation In Transient Electronic Systems, Suk Won Hwang, Seung Kyun Kang, Xian Huang, Mark A. Brenckle, Fiorenzo G. Omenetto

Mechanical and Aerospace Engineering Faculty Research & Creative Works

(Graph Presented). Materials and device designs are presented for electronic systems that undergo functional transformation by a controlled time sequence in the dissolution of active materials and/or encapsulation layers. Demonstration examples include various biocompatible, multifunctional systems with autonomous behavior defined by materials selection and layout.

Passive Symmetry In Dynamic Systems And Walking, Haris Muratagic

USF Tampa Graduate Theses and Dissertations

The ubiquitous nature of symmetry lends itself to be taken for granted, however the breath of research on symmetry encompasses several disciplines. In engineering, studies centered on symmetry often address issues in dynamic systems theory, robotics, and gait rehabilitation. This thesis presents findings on two specific topics dealing with passively induced symmetry; dissimilar rotating systems and human gait. Past studies on passive symmetry in dynamic systems often incorporate physical coupling or a controller. This thesis presents a technique to passively induce symmetry between two dissimilar systems that are not physically connected. This work also presents a human gait study consisting …

The Research, Design And Implementation Of A Remotely Operated Bioreactor With Incubation System For The Purpose Of A 3d Cell Line Growth, Steven Doyle, John Helms, Ryan Longchamps, Azita Amiri

Von Braun Symposium Student Posters

No abstract provided.

Measuring Polydimethylsiloxane (Pdms) Mechanical Properties Using Flat Punch Nanoindentation Focusing On Obtaining Full Contact, Federico De Paoli

USF Tampa Graduate Theses and Dissertations

In this research, the materials used were the Polydimethylsiloxane (PDMS) polymers. PDMS mechanicals properties were measured using a customized version of the nanoindentation test using a flat punch tip. The method is proposed in Chapter 3 and it is used to calculate the elastic modulus of different PDMS samples. The samples tested were both produced specifically for this research and available in the laboratory’s storage. They all present different levels of cross-linking degree.

It is quite common to not have full contact between the cylindrical flat punch and the sample because of the unavoidable tilt. The new method guarantees establishing …

Implementation Of A Novel Hydraulic Hybrid Powertrain In A Sports Utility Vehicle, Michael Sprengel, Tyler Bleazard, Hiral Haria, Monika Ivantysynova

School of Mechanical Engineering Faculty Publications

Hydraulic hybrid transmissions offer an efficient and high performance alternative to electric hybrid transmission in on-road vehicles. One of the principle benefits of hydraulic over electric hybrids is the higher power density offered by their energy storage media. This enables hydraulic hybrids to capture virtually all of the available kinetic energy from braking. In contrast electric hybrids are often forced to dissipate part of this energy through friction brakes due to the lower power density inherent in their energy storage media. To date various hydraulic hybrid architectures have been investigated and put into production. However as is typically true there …

Dynamics Of Non-Circular Finite-Release Gravity Currents, ‪Nadim Zgheib, T. Bonometti, S. Balachandar

Mechanical Engineering Faculty Publications

The present work reports some new aspects of non-axisymmetric gravity currents obtained from laboratory experiments, fully resolved simulations and box models. Following the earlier work of Zgheib et al. (Theor. Comput. Fluid Dyn., vol. 28, 2014, pp. 521–529) which demonstrated that gravity currents initiating from non-axisymmetric cross-sectional geometries do not become axisymmetric, nor do they retain their initial shape during the slumping and inertial phases of spreading, we show that such non-axisymmetric currents eventually reach a self-similar regime during which (i) the local front propagation scales as t1/2 as in circular releases and (ii) the non-axisymmetric front has a self-similar …

Design Of Shape Morphing Structures Using Bistable Elements, Ahmad Alqasimi

USF Tampa Graduate Theses and Dissertations

This dissertation presents new concepts and methodology in designing shape-morphing structures using bistable elements. Developed using the Pseudo-Rigid-Body Model (PRBM), linear bistable compliant mechanism elements produce predictable and controllable length changes. Step-by-step design procedures are developed to guide the design process of these bistable elements. Two different examples of Shape-Morphing Space Frames (SMSFs) were designed and prototyped utilizing the bistable linear elements in a single-layer grid, in addition to flexures and rigid links, to morph a cylindrical space frame into both a hyperbolic and a spherical space frame. Moreover, bistable unit-cell compliant-mechanism elements were also developed to morph a compact …

Why Doesn't 25 Years Of An Evolving Energy Code Make More Of A Difference?, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

This paper was presented at the 2015 Behavior, Energy and Climate Change Conference (BECC). New and more stringent building energy codes are implemented with the assumption and expectation that significant energy conservation will occur. While simulation and various analysis methodologies may be reasonably sound at estimating the energy impact, the actual impact is largely dependent upon new code enforcement and occupant behavior. This work is based upon the research question: Do homes built to a newer energy code deliver measurable energy savings compared to homes built to a much earlier energy code? This residential research study was focused on comparing …

Coalescence-Induced Jumping Of Nanoscale Droplets On Super-Hydrophobic Surfaces, Zhi Liang, Pawel Keblinski

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Coalescence-Induced Jumping of Tens of Microns Size Droplets on Super-Hydrophobic Surfaces Has Been Observed in Both Experiments and Simulations. However, Whether the Coalescence-Induced Jumping Would Occur for Smaller, Particularly Nanoscale Droplets, is an Open Question. using Molecular Dynamics Simulations, We Demonstrate that in Spite of the Large Internal Viscous Dissipation, Coalescence of Two Nanoscale Droplets on a Super-Hydrophobic Surface Can Result in a Jumping of the Coalesced Droplet from the Surface with a Speed of a Few M/s. Similar to the Coalescence-Induced Jumping of Microscale Droplets, We Observe that the Bridge between the Coalescing Nano-Droplets Expands and Impacts the …

Sub-Millisecond Measurements Of Thermal Conductivity And Thermal Diffusivity Using Micrometer-Sized Hot Strips, Mattias K. Gustavsson, Johan S. Gustavsson, Yi Ma, Åsa Haglund, Daniel Cederkrantz, Silas E. Gustafsson

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

A new measurement technique based on the transient hot strip technique has recently been developed for studying anisotropic thermal transport properties of thin crystalline films. A micrometer-sized hot strip sensor is evaporated on the surface of the crystalline film sample, which has been deposited on a substrate wafer of limited thickness. From a pulsed transient recording, using sub-millisecond square-shaped pulses, a thermal probing depth that is less than the film thickness is assured. In the ongoing work of verifying the technique, we show results from measurements on z-cut crystal quartz and fused silica, using thermal probing depths of only 30 …

High-Temperature Thermal Properties Using Reflected Sample Generated Radiation, E. G. Wolff

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

A method for determining high-temperature thermal properties of thick solid materials involves short-term radiation pulses (20–200 s) on the front surface of a sample via a light guide, such as a quartz or sapphire rod. The magnitude of the flux absorbed must be accurately known for thermal conductivity, but not for thermal diffusivity. Power sources may include a lamp or laser but each has difficulties. For example, a lamp often has too little power and needs complex optics, and a laser beam may have excessive power that also lacks control. A heated sample transmits considerable radiation that varies with temperature …

Provisional Assessment Of Candidate High-Temperature Thermal Conductivity Reference Materials In The Emrp “Thermo” Project, J. Wu, R. Morrell, T. Fry, S. Gnaniah, D. Gohil, A. Dawson, J. Hameury, Alain Koenen, U. Hammerschmidt, E. Turzó-András, R. Strnad, A. Blahut

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

This article describes the provisional assessment of a short list of four candidate high-temperature thermal conductivity reference materials in a European research project, “Thermo.” These four candidate materials are low-density calcium silicate, amorphous silica, high-density calcium silicate, and exfoliated vermiculite. Based on initial tests on material composition and microstructure changes, dimensional stability, mechanical stability, chemical stability and uniformity, the best two candidate materials that would be considered for further detailed characterization in the next stage are low-density calcium silicate and high-density calcium silicate. These two materials are dimensionally, mechanically, and chemically stable, which are more robust and easier to handle …

Simulation And Optimization Of An In-Plane Thermal Conductivity Measurement Structure For Silicon Nanostructures, Y. Zeng, Amy Marconnet

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

Silicon-on-insulator based measurement structures have recently been developed to measure the thermal conductivity of nanostructured materials. For example, suspended steady-state measurement structures are often used for measuring the in-plane thermal conductivity of thin silicon films as the heat transfer is confined to the lateral direction. However, few researchers have focused on optimizing the important structural and measurement parameters, such as geometry and applied heater power levels, to ensure accurate measurements. In this article, numerical simulations are first compared with existing experimental data for suspended steady-state joule heating measurement structures with a large suspended region (~10 mm²). Then, a …

Design Of A Guarded Hot Plate For Measuring Thin Specimens Of Polymer And Composite Materials, Clark Stacey, M. J. Parfitt, A. J. Simpkin, J. Wu

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

The National Physical Laboratory (NPL) has developed a new design of guarded hot plate apparatus specifically for absolute measurements on thin specimens of medium thermal conductivity materials, such as the polymer composites that are becoming more widely used in aerospace and other advanced manufacturing sectors. Although NPL has an existing measurement facility based on a commercially manufactured apparatus conforming to ASTM E1530, this current facility is not based on an absolute measurement technique and is not able to provide the low measurement uncertainty or flexibility that is increasingly being demanded by industrial users of this NPL service.

The target specification …

International Comparison Of Guarded Hot Plate Facilities At Low Temperature On Mineral Wool Insulation Material, Alain Koenen, Clark Stacey, Erik Rasmussen, Roland Schreiner, Grażyna Swołek

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

In 2000, the Institute for Reference Materials and Measurements (IRMM) proposed the creation of a new European certified reference material for the thermal conductivity measurements IRMM-440. A specific production batch of high density (64–78 kg/m³) resin-bonded glass fiber boards was manufactured and characterized by a group of six leading European laboratories with long-standing expertise in thermal conductivity measurements, including four national measurements institutes. The IRMM-440 has since been used as the European certified reference material for thermal conductivity measurements on thermal insulation covering temperatures between –10°C and 50°C, and most frequently to calibrate Heat Flow Meter apparatus making …

A New Facility For The Experimental Investigation On Nano Heat Transfer Between Gas Molecules And Ceramic Surfaces, D. Bayer, U. Gross, K. Raed

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

Since the last decade, the interest has risen in nanoscaled technological products, which have advantages through their size effect. The size effect also plays a significant role in the area of micro- and nanoscale heat transfers. Many applications were developed using this effect, such as nanostructured porous media, e.g. Aerogels or ceramics. This experimental work is focused on the determination of thermal accommodation coefficients (TAC) on ceramic surfaces considering several influencing factors. TAC is influenced by temperature, kind of gas, kind of wall material, roughness, and contamination with adsorbed gas layers. To determine TAC, a parallel plate apparatus is used, …

Heat Transfer Mechanisms In Porous Materials And Contemporary Problems In Thermophysical Properties Investigations: Analyses And Solutions, E. Litovsky, V. Issoupov, J. Kleiman

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

This article is an overview of the topical problems in the investigation of thermophysical properties and the development of a database for porous materials. Determination of both apparent/measured and true thermophysical properties is discussed taking into account combined heat and mass transfer, latent heat effects during chemical and physical transformations, as well as structural changes. The approaches to the solution of these problems are demonstrated for a number of different classes of materials:

1. Industrial refractories, ceramics, highly porous insulation;
2. Moist materials and materials undergoing phase, chemical and structural transformations;
3. Materials semitransparent for heat radiation.

The approaches being used in the …

On The Development Of The Hot Strip, Hot Disc, And Pulse Hot Strip Methods For Measuring Thermal Transport Properties, Silas E. Gustafsson

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

This review is focused on the development of experimental methods for measuring thermal transport properties. Special emphasis is given to plane probes, which are used both as heat sources and as temperature recording devices. With such probes it is under certain conditions possible to determine both the thermal conductivity and the thermal diffusivity from a single transient recording. The conditions which must be fulfilled in an experiment are introduced by the use of the concept of a thermal probing depth, and from which the time window of observations can be defined. The ultimate goal of the dual determination of the …

Designing A Mechanically Robust Thermoelectric Module For High Temperature Application, Amirkoushyar Ziabari, Kazuaki Yazawa, Ali Shakouri

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

We report a numerical study on the impacts of variations in the geometry, boundary conditions, and the coefficient of thermal expansion of the materials on the maximum shearing stress in thermoelectric power generator module (TEM) for high temperature applications. The maximum shearing stress in the TEM is evaluated for different designs focusing on their dependency on the fill factor. Although predictions by the previously developed analytical modeling are in partial agreement with numerical results, simplifying assumptions for the analytical model can limit the range of validity. Our numerical analysis shows that reduction of the fill factor alone under all the …

Simulation And Analysis Of An Integrated Device To Simultaneously Characterize Thermal And Thermoelectric Properties, Collier Miers, Amy Marconnet

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

For many applications, multiple material properties impact device performance and characterization of multiple properties using a single sample is desirable. In this article, the authors focus on thermoelectric materials characterization, which requires the thermal conductivity, electrical conductivity, and Seebeck coefficient to be quantified. Specifically, the authors present a design analysis using numerical COMSOL simulations of the 3w technique to optimize a measurement structure for thermoelectric films while also including the capability for electrical measurements to be performed on the same sample without detachment or repositioning. Thermal optimization of the structure is achieved through investigation of temperature spatial uniformity, the …

Role Of Thermal Conductivity For Thermoelectrics With Finite Contacts, Yee Rui Koh, Kazuaki Yazawa, Ali Shakouri

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

The role of thermal conductivity in the performance of thermoelectric (TE) devices as compared to other material properties such as Seebeck coefficient and the electrical conductivity will be discussed. A TE energy conversion system that includes thermal contacts for the hot side and the cold side with finite heat transfer performances is considered. Some of the trends in electronics cooling applications have been described. In this article, the effect of material properties as a function of energy current flow direction will be focused.

TEs have an advantage as solid-state heat energy conversion devices especially for applications with spatial constraints. A …

Comparative Testing Of Thermal Conductivity For Thermal Insulation Products: The European Keymark Experience For More Than 50 Equipment At 25 Test Institutes, Erik Rasmussen, Clark Stacey, Alain Koenen, Eva-Lotta W. Kurkinen

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

This article describes comparative testing of thermal conductivity on a range of thermal insulation products used in the construction of buildings. This testing was arranged by the CEN Keymark scheme for voluntary certification of insulation within Europe, and measurements have been performed using over 50 instruments in more than 25 registered laboratories.

The uniformity of the material and a unique thermal conductivity value for each set of test specimens that were used in the comparison have been established according to the Keymark scheme rules, which were developed by experts from the most respected European laboratories. These experts include most of …

Determination Of The Thermal Resistance Of Pipe Insulation Material From Thermal Conductivity Of Flat Insulation Products, Alain Koenen, Damien M. Marquis

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

New European product standards now include a mandatory requirement for manufacturers to declare the temperature-dependent thermal conductivity for each insulation used in building equipments and industrial installations. For pipe insulation systems, the measurement is usually performed by a standard pipe test method, in which the value on a large temperature range is integrated to reduce temperature range and improve temperature measurement control. The alternative proposed in this article consists in determining the thermal conductivity of a pipe insulation system from the results measured on a flat slab specimen. The protocol used in this study consists in collecting the thermal conductivity …

Flexible Buffer Materials To Reduce Contact Resistance In Thermal Insulation Measurements, R. E. Clarke, G. Rosengarten, B. Shabani

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

Thermal insulation test methods approach their lower limits as thermal resistance falls below 0.1 m²⋅K/W. This is the minimum value specified in ASTM C 518 (ASTM International, 2010b) while ASTM C 177 (ASTM International, 2010a) proposes about 0.06 m²⋅K/W. Nevertheless these are the test methods, along with their ISO equivalents, required by Australasian building codes and directed at many products and materials with thermal resistance on the low side of 0.1 m²⋅K/W. Alternatives, such as ASTM E 1530 (ASTM International, 2011), cover much lower resistances but require carefully prepared small specimens and very-high contact …

Bilateral National Metrology Institute Comparison Of Guarded-Hot-Plate Apparatus, Alain Koenen, Robert R. Zarr, William F. Guthrie

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

Two national metrology institutes have conducted an international interlaboratory comparison on thermal conductivity for two thermal insulation reference materials. The Laboratoire national de métrologie et d’essais (LNE), France, and the National Institute of Standards and Technology (NIST), United States, present measurements obtained by the guarded-hot-plate method. The study involved two materials: expanded polystyrene board (EPS) and fibrous glass board (FGB). The EPS was provided by the LNE and is issued as a transfer specimen; the FGB provided by NIST was issued as Standard Reference Material (SRM) 1450c. For each reference material, the study was based on four independent measurements at …

Plenary Talks, General Sessions, And Session Chairs, Timothy S. Fisher, Amy Marconnet

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

No abstract provided.

In Memoriam, Timothy S. Fisher, Amy Marconnet

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

No abstract provided.

Foreword, Timothy S. Fisher, Amy Marconnet

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES)

No abstract provided.