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1143 full-text articles. Page 1 of 46.

Energy Efficient Process Heating: Insulation And Thermal Mass, Kevin Carpenter, J. Kelly Kissock 2017 Energy & Resource Solutions

Energy Efficient Process Heating: Insulation And Thermal Mass, Kevin Carpenter, J. Kelly Kissock

J. Kelly Kissock

Open tanks and exterior surfaces of process heating equipment lose heat to the surroundings via convection, radiation, and/or evaporation. A practical way of reducing heat loss is by insulating or covering the surfaces. This paper presents methods to quantify heat loss and energy savings from insulating hot surfaces and open tanks. The methods include radiation and evaporation losses, which are ignored by simplified methods. In addition, thermal mass, such as refractory, conveyor and racking equipment, acts as a heat sink and increases heating energy use in process heating applications. This paper presents lumped capacitance and finite-difference methods for estimating ...


Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock 2017 Energy & Resource Solutions

Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock

J. Kelly Kissock

Much energy is lost through excess air flow in and out of process heating equipment. Energy saving opportunities from managing air flow include minimizing combustion air, preheating combustion air, minimizing ventilation air, and reconfiguring openings to reduce leakage.

This paper identifies these opportunities and presents methods to quantify potential energy savings from implementing these energy-savings measures. Case study examples are used to demonstrate the methods and the potential energy savings.The method for calculating savings from minimizing combustion air accounts for improvement in efficiency from increased combustion temperature and decreased combustion gas mass flow rate.

The method for calculating savings ...


Effect Of Sky Conditions On Light Transmission Through A Suspended Particle Device Switchable Glazing, Aritra Ghosh, Brian Norton, Aidan Duffy 2017 Dublin Institute of Technology

Effect Of Sky Conditions On Light Transmission Through A Suspended Particle Device Switchable Glazing, Aritra Ghosh, Brian Norton, Aidan Duffy

Articles

A suspended particle device (SPD) switchable glazing changes its state from opaque to transparent in the presence of a power supply. SPD glazing's near normal transmission varies with incident angle and clearness index. Due to a lower diffuse component, higher glazing transmission ensues at higher clearness indices. Transmittance values for different azimuthal incident angle for a SPD glazing for its “transparent” and “opaque” states have been determined. In Dublin, below 0.5 clearness index, isotropic diffuse transmittance was prevailed while transmission of direct insolation was dominant above 0.5 clearness index. For south facing vertical plane SPD glazing transmittance ...


A Mechanical Regenerative Brake And Launch Assist Using An Open Differential And Elastic Energy Storage, David H. Myszka, Andrew P. Murray, Kevin Giaier, Vijay Krishna Jayaprakash, Christoph Gillum 2017 University of Dayton

A Mechanical Regenerative Brake And Launch Assist Using An Open Differential And Elastic Energy Storage, David H. Myszka, Andrew P. Murray, Kevin Giaier, Vijay Krishna Jayaprakash, Christoph Gillum

David Myszka

Regenerative brake and launch assist (RBLA) systems are used to capture kinetic energy while a vehicle decelerates and subsequently use that stored energy to assist propulsion. Commercially available hybrid vehicles use generators, batteries and motors to electrically implement RBLA systems. Substantial increases in vehicle efficiency have been widely cited. This paper presents the development of a mechanical RBLA that stores energy in an elastic medium. An open differential is coupled with a variable transmission to store and release energy to an axle that principally rotates in a single direction. The concept applies regenerative braking technology to conventional automobiles equipped with ...


A Mechanical Regenerative Brake And Launch Assist Using An Open Differential And Elastic Energy Storage, David H. Myszka, Andrew P. Murray, Kevin Giaier, Vijay Krishna Jayaprakash, Christoph Gillum 2017 University of Dayton

A Mechanical Regenerative Brake And Launch Assist Using An Open Differential And Elastic Energy Storage, David H. Myszka, Andrew P. Murray, Kevin Giaier, Vijay Krishna Jayaprakash, Christoph Gillum

Andrew P. Murray

Regenerative brake and launch assist (RBLA) systems are used to capture kinetic energy while a vehicle decelerates and subsequently use that stored energy to assist propulsion. Commercially available hybrid vehicles use generators, batteries and motors to electrically implement RBLA systems. Substantial increases in vehicle efficiency have been widely cited. This paper presents the development of a mechanical RBLA that stores energy in an elastic medium. An open differential is coupled with a variable transmission to store and release energy to an axle that principally rotates in a single direction. The concept applies regenerative braking technology to conventional automobiles equipped with ...


Abstract Template Resrb 2017, Wojciech M. Budzianowski 2016 Wroclaw University of Technology

Abstract Template Resrb 2017, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Order Form Resrb 2017, Wojciech M. Budzianowski 2016 Wroclaw University of Technology

Order Form Resrb 2017, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


C.V., Wojciech M. Budzianowski 2016 Wroclaw University of Technology

C.V., Wojciech M. Budzianowski

Wojciech Budzianowski

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Photovoltaic Cooking In The Developing World, Tyler Watkins, Christopher O'Day, Omar Arriaga 2016 California Polytechnic State University, San Luis Obispo

Photovoltaic Cooking In The Developing World, Tyler Watkins, Christopher O'Day, Omar Arriaga

Mechanical Engineering

The challenge of clean cooking is faced by hundreds of millions of people worldwide. We present a cooking technology consisting of a solar panel directly connected to an electric heater in a well-insulated chamber. Assuming continued decrease in solar panel prices, we anticipate that in a few decades Solar Electric Cooking technologies will be the most common cooking technology for the poor. Appropriate use of insulation reduces the power demand making low-power Insulated Solar Electric Cooking systems already cost competitive.


Fundamental Studies Of Electrochemical Reactions And Microfluidics In Proton Exchange Membrane Electrolyzer Cells, Jingke Mo 2016 University of Tennessee, Knoxville

Fundamental Studies Of Electrochemical Reactions And Microfluidics In Proton Exchange Membrane Electrolyzer Cells, Jingke Mo

Doctoral Dissertations

In electrochemical energy devices, including fuel cells, electrolyzers and batteries, the electrochemical reactions occur only on triple phase boundaries (TPBs). The boundaries provide the conductors for electros and protons, the catalysts for electrochemical reactions and the effective pathways for transport of reactants and products. The interfaces have a critical impact on the overall performance and cost of the devices in which they are incorporated, and therefore could be a key feature to optimize in order to turn a prototype into a commercially viable product. For electrolysis of water, proton exchange membrane electrolyzer cells (PEMECs) have several advantages compared to other ...


Investigation Of Low Reynolds Number Flow And Heat Transfer Of Louvered Surfaces, Pradeep R. Shinde 2016 Florida International University

Investigation Of Low Reynolds Number Flow And Heat Transfer Of Louvered Surfaces, Pradeep R. Shinde

FIU Electronic Theses and Dissertations

This study focuses on the investigation of flow behavior at low Reynolds numbers by the experimental and numerical performance testing of micro-channel heat exchangers. An experimental study of the heat transfers and pressure drop of compact heat exchangers with louvered fins and flat tubes was conducted within a low air-side Reynolds number range of 20 < ReLp < 225. Using an existing low-speed wind tunnel, 26 sample heat exchangers of corrugated louver fin type, were tested. New correlations for Colburn j and Fanning friction f factor have been developed in terms of non-dimensional parameters. Within the investigated parameter ranges, it seems that both the j and f factors are better represented by two correlations in two flow regimes (one for ReLp = 20 – 80 and one for ReLp = 80 – 200) than a single regime correlation in the power-law format. The results support the conclusion that airflow and heat transfer at very low Reynolds numbers behaves differently from that at higher Reynolds numbers ...


Behaviour Of A Spd Switchable Glazing In An Outdoor Test Cell With Heat Removal Under Varying Weather Conditions, Aritra Ghosh, Brian Norton, Aidan Duffy 2016 Dublin Institute of Technology

Behaviour Of A Spd Switchable Glazing In An Outdoor Test Cell With Heat Removal Under Varying Weather Conditions, Aritra Ghosh, Brian Norton, Aidan Duffy

Articles

Suspended particle device (SPD) switchable glazing has potential to control transmission of solar radiation in the visible range by changing its transparency from 55% to 5%. Outdoor test cell characterisation of a SPD switchable glazing offered the dynamic solar heat gain coefficient (SHGC) which varied between 0.05 (when opaque) and 0.38 (when transparent). Reduction of maximum temperature rise of 11% and 15% was possible using SPD “transparent” and “opaque” state compared to same area double-glazing. Insulated test cell with water flow heat exchanger was employed to measure the cooling load reduction potential of SPD glazing while its transmission ...


Modeling Pyrolysis Of Large Coal Particles With Many Species, Jianqing Li 2016 Marquette University

Modeling Pyrolysis Of Large Coal Particles With Many Species, Jianqing Li

Master's Theses (2009 -)

Coal currently supplies 40% of the world’s electricity needs, and is one of the most important energy sources. As the initial stage of coal combustion, pyrolysis is a thermal decomposition process which converts coal into light gases and tars, which are subsequently consumed in combustion reactions, as well as solid char. Recently there has been interest in using slow pyrolysis as a stand-alone process for the production of chemicals and fuels from large (mm-scale) coal particles. Simulations can be used to efficiently study the impact of pyrolysis conditions on gas, tar and char yields, as well as gas and ...


Rate Coefficients Of The Reaction Of Oh With Allene And Propyne At High Temperatures, Et-touhami Es-sebbar, Fethi Khaled, Ahmed Elwardany, Aamir Farooq 2016 Paul Scherrer Institute (PSI)

Rate Coefficients Of The Reaction Of Oh With Allene And Propyne At High Temperatures, Et-Touhami Es-Sebbar, Fethi Khaled, Ahmed Elwardany, Aamir Farooq

Dr. Et-touhami Es-sebbar

Allene (H2C=C=CH2; a-C3H4) and propyne (CH3C=CH; p-C3H4) are
important species in various chemical environments. In combustion processes, the
reactions of hydroxyl radicals with a-C3H4 and p-C3H4 are critical in the overall fuel
oxidation system. In this work, rate coefficients of OH radicals with allene (OH + H2C=
C=CH2 → products) and propyne (OH + CH3C=CH → products) were measured
behind reflected shock waves over the temperature range of 843−1352 K and pressures
near 1.5 atm. Hydroxyl radicals were generated by rapid thermal decomposition of tertbutyl
hydroperoxide ((CH3)3−CO−OH), and monitored by narrow line width laser ...


Coke Oven Emissions: A Case Study Of Technology-Based Regulation, John D. Graham, David R. Holtgrave 2016 University of New Hampshire

Coke Oven Emissions: A Case Study Of Technology-Based Regulation, John D. Graham, David R. Holtgrave

RISK: Health, Safety & Environment

After examining and analyzing the experience with coke ovens, the authors conclude that attempts to force technology beyond its demonstrated competence can be both expensive and ineffective in controlling hazards. They also suggest implications for pending proposals to further control air pollution.


Industrial Solid-State Energy Harvesting: Mechanisms And Examples, Matthew Kocoloski, Carl Eger, Robin McCarty, Kevin P. Hallinan, J. Kelly Kissock 2016 Carnegie Mellon University

Industrial Solid-State Energy Harvesting: Mechanisms And Examples, Matthew Kocoloski, Carl Eger, Robin Mccarty, Kevin P. Hallinan, J. Kelly Kissock

J. Kissock

This paper explores the potential for solid-state energy harvesting in industrial applications. In contrast to traditional heat recovery, the output of solid-state devices is electricity, which can be readily used in virtually any plant. The progress in harvesting waste heat via thermoelectric and thermionic generators is described. With second law efficiencies now approaching 50% and 80% respectively, we show that these technologies are on the cusp of practical use. Finally, we present an example of energy harvesting using thermionic devices in an industrial application. The example considers energy harvesting from a furnace at a glass manufacturing facility where exhaust gases ...


The Key Ideas Of Mdw Viii: A Summary, Aaron Altman, Clive L. Dym, Ray Hurwitz, John W. Wesner 2016 University of Dayton

The Key Ideas Of Mdw Viii: A Summary, Aaron Altman, Clive L. Dym, Ray Hurwitz, John W. Wesner

Aaron Altman

This paper summarizes and highlights the presentations and discussions that took place during Mudd Design Workshop VIII, ‘Design Education: Innovation and Entrepreneurship,’ at Harvey Mudd College. This paper also describes both the key ideas that emerged from the presentations and discussions of the participating engineering design educators, practitioners and researchers, and the methodology used to capture and retain those ideas. Additionally, this paper proposes a framework of design competencies that were created and evolved by the workshop’s participants as a response to a question posed at one of the workshop sessions: ‘What are the minimum design competencies students should ...


Design Methodology For Low Speed High Altitude Long Endurance Unmanned Aerial Vehicles, Aaron Altman 2016 University of Dayton

Design Methodology For Low Speed High Altitude Long Endurance Unmanned Aerial Vehicles, Aaron Altman

Aaron Altman

High Altitude Long Endurance (HALE) Unmanned Aerial Vehicles (UAV's) are increasingly being considered to perform a wide range of tasks. Recent years have seen greater value of UAV's in the military reconnaissance arena, first in the Persian Gulf war, with the use of small UAV's, and more recently over Bosnia with medium sized UAV's.

The NASA ERAST program uses HALE UAV's for environmental sensing and monitoring. The military has investigated using HALE UAV's for Theater Ballistic Missile defense, as well as general battlefield reconnaissance. Proposals have been made to use HALE UAV's for ...


Wing Tip Vortices From An Exergy-Based Perspective, Muhammad Omar Memon, Kevin Wabick, Aaron Altman, Rainer M. Buffo 2016 University of Dayton

Wing Tip Vortices From An Exergy-Based Perspective, Muhammad Omar Memon, Kevin Wabick, Aaron Altman, Rainer M. Buffo

Aaron Altman

The lens of exergy is used to investigate a wingtip vortex in the near wake over a range of angles of attack. Exergy is the measure of thermodynamically “available” energy as determined through the more discriminating second law of thermodynamics. Experiments were conducted in a water tunnel at Institute of Aerospace Systems at Aachen.

The data were taken three chord lengths downstream in the Trefftz plane of an aspect ratio 5 Clark-Y wing with a square-edged wing tip using particle image velocimetry. Intuitively, the minimum available energy state is expected to correspond to the maximum lift-to-drag ratio angle of attack ...


A Multi-Directional Treadmill Training Program For Improving Gait, Balance, And Mobility In Individuals With Parkinson’S Disease: A Case Series, Kimberly Smith, Kurt Jackson, Kimberly Edginton Bigelow, Lloyd L. Laubach 2016 University of Dayton

A Multi-Directional Treadmill Training Program For Improving Gait, Balance, And Mobility In Individuals With Parkinson’S Disease: A Case Series, Kimberly Smith, Kurt Jackson, Kimberly Edginton Bigelow, Lloyd L. Laubach

Kimberly Edginton Bigelow

Treadmill training is a commonly used intervention for improving gait in people with Parkinson’s disease (PD). However, little is known about how treadmill training may also influence balance and other aspects of mobility.

The purpose of this case series was to explore the feasibility and possible benefits of multi-directional treadmill training for individuals with PD. Four participants (62.3 ± 6.5 yrs, Hoehn & Yahr 2-4) performed 8 weeks of treadmill training 3 times per week. Weeks 1-4 included forward walking only, while weeks 5-8 included forward and multi-directional walking. Participants were tested every 4 weeks on 4 separate occasions ...


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