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Energy Systems

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2011

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Full-Text Articles in Mechanical Engineering

Energy Savings And Peak Demand Reduction Of A Seer 21 Heat Pump Vs. A Seer 13 Heat Pump With Attic And Indoor Duct Systems - December 2011, Florida Solar Energy Center, James Cummings Dec 2011

Energy Savings And Peak Demand Reduction Of A Seer 21 Heat Pump Vs. A Seer 13 Heat Pump With Attic And Indoor Duct Systems - December 2011, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Experiments were run in an unoccupied 1600 ft2 house, the Manufactured Housing (MH Lab) at the Florida Solar Energy Center (FSEC), to evaluate the delivered performance as well as the relative performance of a SEER 21 variable capacity heat pump versus a SEER 13 heat pump. The performance was evaluated with two different duct systems: a standard attic duct system and an indoor duct system located in a dropped-ceiling space.


Analysis Of Biomass/Coal Co-Gasification For Integrated Gasification Combined Cycle (Igcc) Systems With Carbon Capture, Henry A. Long Iii Dec 2011

Analysis Of Biomass/Coal Co-Gasification For Integrated Gasification Combined Cycle (Igcc) Systems With Carbon Capture, Henry A. Long Iii

University of New Orleans Theses and Dissertations

In recent years, Integrated Gasification Combined Cycle Technology (IGCC) has become more common in clean coal power operations with carbon capture and sequestration (CCS). Great efforts have been spent on investigating ways to improve the efficiency, reduce costs, and further reduce greenhouse gas emissions. This study focuses on investigating two approaches to achieve these goals. First, replace the subcritical Rankine steam cycle with a supercritical steam cycle. Second, add different amounts of biomass as feedstock to reduce emissions. Finally, implement several types of CCS, including sweet- and sour-shift pre-combustion and post-combustion.

Using the software, Thermoflow®, this study shows that utilizing …


2011 Fall Engr333 Project Final Report, Fall 2011 Engr333 Dec 2011

2011 Fall Engr333 Project Final Report, Fall 2011 Engr333

ENGR 333

Analysis of the Bunker Interpretive Center (BIC) began during the spring of 2011 with the Engineering 382 Instrumentation Lab. To determine the energy use at the BIC, sensing equipment was placed on 44 different energy consuming devices, ranging from pumps to lights to heating and ventilation (HVAC) equipment. These data were collected over the spring and summer and then analyzed by the Engineering 333 Thermal Systems Design class during the fall of 2011. The class was tasked with determining whether or not the BIC was eligible for Energy Star certification. While the building was built to be LEED Gold certified, …


2011 Fall Engr333 Student Seminar Presentation, 2011 Fall Engr333 Dec 2011

2011 Fall Engr333 Student Seminar Presentation, 2011 Fall Engr333

ENGR 333

File for student presentation, given by students in the Fall 2010 class of ENGR333.


Robust Multichannel Functional-Data-Analysis Methods For Data Recovery In Complex Systems, Jian Sun Dec 2011

Robust Multichannel Functional-Data-Analysis Methods For Data Recovery In Complex Systems, Jian Sun

Doctoral Dissertations

In recent years, Condition Monitoring (CM), which can be performed via several sensor channels, has been recognized as an effective paradigm for failure prevention of operational equipment or processes. However, the complexity caused by asynchronous data collection with different and/or time-varying sampling/transmission rates has long been a hindrance in the effective use of multichannel data in constructing empirical models. The problem becomes more challenging when sensor readings are incomplete. Traditional sensor data recovery techniques are often prohibited in asynchronous CM environments, not to mention sparse datasets. The proposed Functional Principal Component Analysis (FPCA) methodologies, e.g., nonparametric FPC model and semi-parametric …


23 - از بين بردن بافتهاي سرطاني به وسيله امواج فراصوت کانوني با شدت بالا, Roya Samanipour, Mehdi Maerefat, Manizheh Mokhtari-Dizaji, Alireza Zolfaghari Dec 2011

23 - از بين بردن بافتهاي سرطاني به وسيله امواج فراصوت کانوني با شدت بالا, Roya Samanipour, Mehdi Maerefat, Manizheh Mokhtari-Dizaji, Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.


Designing Carbon Taxation Schemes For Automobiles: A Simulation Exercise For Germany, Adamos Adamou, Sofronis Clerides, Theodoros Zachariadis Dec 2011

Designing Carbon Taxation Schemes For Automobiles: A Simulation Exercise For Germany, Adamos Adamou, Sofronis Clerides, Theodoros Zachariadis

Theodoros Zachariadis

Vehicle taxation based on CO2 emissions is increasingly being adopted worldwide in order to shift consumer purchases to low-carbon cars, yet little is known about the effectiveness and overall economic impact of these schemes. We focus on feebate schemes, which impose a fee on high-carbon vehicles and give a rebate to purchasers of low-carbon automobiles. We estimate a discrete choice model of demand for automobiles in Germany and simulate the impact of alternative feebate schemes on emissions, consumer welfare, public revenues and firm profits. The analysis shows that a well-designed scheme can lead to emission reductions without reducing overall welfare.


Lectio Praecursoria, Kari Myöhänen Dec 2011

Lectio Praecursoria, Kari Myöhänen

Kari Myöhänen

Lectio praecursoria: Modelling of combustion and sorbent reactions in three-dimensional flow environment of a circulating fluidized bed furnace


Energy-Based Analysis Of Utility Scale Hybrid Power Systems, Kwame Agyenim-Boateng Dec 2011

Energy-Based Analysis Of Utility Scale Hybrid Power Systems, Kwame Agyenim-Boateng

UNLV Theses, Dissertations, Professional Papers, and Capstones

The promise of large-scale use of renewables such as wind and solar for supplying electrical power is tempered by the sources' transient behavior and the impact this would have on the operation of the grid. Among the methods cited for addressing some of those concerns are exploring the complementary nature of solar and wind power generation, and through the use of supplemental energy storage. While the technology for the latter has not been proven to be economical on a large scale at the present time, some assessments of what magnitude is required can be made. An energy-based analysis of utility …


Wireless Solar-Powered Thermal Imaging Camera, Andy Bonk, Billy Mcvicker, Jacob Richardson Dec 2011

Wireless Solar-Powered Thermal Imaging Camera, Andy Bonk, Billy Mcvicker, Jacob Richardson

Mechanical Engineering

Creation of a mounted wireless self-powered thermal imaging camera system.


Development Of A Scale Model Wind Turbine For Testing Of Offshore Floating Wind Turbine Systems, Heather Rae Martin Dec 2011

Development Of A Scale Model Wind Turbine For Testing Of Offshore Floating Wind Turbine Systems, Heather Rae Martin

Electronic Theses and Dissertations

This thesis presents the development of a 1/50th scale 5 MW wind turbine intended for wind and wave basin model testing of commercially viable floating wind turbine structures. The design is based on a popular 5 MW wind turbine designed by the National Renewable Energy Laboratory (NREL) commonly utilized in numerical modeling efforts. The model wind turbine is to accompany generic floating model platforms for basin model testing. The ultimate goal of the model development testing program is to collect data for validating various floating wind turbine simulation codes such as those developed by NREL. This thesis will present an …


Development Of A Structured Concrete Thermocline Thermal Energy Storage System, Bradley M. Brown Dec 2011

Development Of A Structured Concrete Thermocline Thermal Energy Storage System, Bradley M. Brown

Graduate Theses and Dissertations

The past couple of decades have shown a concern when considering the way the world obtains its power. The focus has been switching from fossil fuels that have been used for hundreds of years to renewable energy sources, such as the sun. Solar energy is readily and infinitely available for harnessing. One problem with solar energy, though, is its inability to be used during the night time and during cloud covered weather. A solution to this problem is the use of energy storage mechanisms. For solar plants that use solar thermal energy (concentrating solar power plants), thermal energy storage (TES) …


Turbine, Vijaya Krushna Varma Mr Nov 2011

Turbine, Vijaya Krushna Varma Mr

VIJAYA KRUSHNA VARMA Mr

Varma designed ultra modern and high efficiency turbines which can use gas, steam or fuels as feed to produce electricity or mechanical work for wide range of usages and applications in industries or at work sites. Varma turbine engines can be used in all types of vehicles. These turbines can also be used in aircraft, ships, battle tanks, dredgers, mining equipment, earth moving machines etc, Salient features of Varma Turbines. 1. Varma turbines are simple in design, easy to manufacture, easy to operate and maintain. 2. Varma turbines are less expensive. 3. Varma turbines have a great power to weight …


Pulsed Fusion And Radiation-Cooled Gaseous Core Fission Rocket Performance Comparisons For A Mars Roundtrip Mission, Miles Owen Oct 2011

Pulsed Fusion And Radiation-Cooled Gaseous Core Fission Rocket Performance Comparisons For A Mars Roundtrip Mission, Miles Owen

Von Braun Symposium Student Posters

No abstract provided.


An Overview Of Sustainable Universities, B Bakhtyar Oct 2011

An Overview Of Sustainable Universities, B Bakhtyar

B Bakhtyar

This book covers definitions, concept, and history of sustainable development (SD), sustainability in higher education (SHE) or sustainable campus, its related theories, history of SHE and the components of SHE, community aspect of SHE or sustainable community, the similarities and differences of cities and university campuses as well as different existing assessment approaches in the world. Moreover, different interpretation of SD, SHE, and their principal and components are introduced. It attempts to give a clear perspective on the history, definitions and different approaches of SHE. Finally, it describes the birth of SD and SHE and their existing status in the …


Technical Note: Friction Factor Diagrams For Pipe Flow, Jim Mcgovern Oct 2011

Technical Note: Friction Factor Diagrams For Pipe Flow, Jim Mcgovern

Articles

This technical note describes diagrams of friction factor for pipe flow that have been prepared using, mainly, the equations that Lewis Moody used to prepare his famous diagram in 1944. The preparation of the new diagrams was prompted by the need for vector graphics versions that could be used for teaching purposes and that could be distributed freely to students and others under a Creative Commons Attribution-Share-Alike license. Using a structure very similar to that of Moody's diagram, variants with the Darcy friction factor and the Fanning friction factor have been prepared. In addition, variants have been prepared that include …


3d Simulation Of Wind Turbine Rotors At Full Scale. Part Ii: Fluid–Structure Interaction Modeling With Composite Blades, Y. Bazilevs, Ming-Chen Hsu, J. Kiendel, R. Wuchner, K. U. Bletzigner Oct 2011

3d Simulation Of Wind Turbine Rotors At Full Scale. Part Ii: Fluid–Structure Interaction Modeling With Composite Blades, Y. Bazilevs, Ming-Chen Hsu, J. Kiendel, R. Wuchner, K. U. Bletzigner

Ming-Chen Hsu

In this two-part paper, we present a collection of numerical methods combined into a single framework, which has the potential for a successful application to wind turbine rotor modeling and simulation. In Part 1 of this paper we focus on: 1. The basics of geometry modeling and analysis-suitable geometry construction for wind turbine rotors; 2. The fluid mechanics formulation and its suitability and accuracy for rotating turbulent flows; 3. The coupling of air flow and a rotating rigid body. In Part 2, we focus on the structural discretization for wind turbine blades and the details of the fluid–structure interaction computational …


High-Performance Computing Of Wind Turbine Aerodynamics Using Isogeometric Analysis, Ming-Chen Hsu, Ido Akkerman, Yuri Bazilevs Oct 2011

High-Performance Computing Of Wind Turbine Aerodynamics Using Isogeometric Analysis, Ming-Chen Hsu, Ido Akkerman, Yuri Bazilevs

Ming-Chen Hsu

In this article we present a high-performance computing framework for advanced flow simulation and its application to wind energy based on the residual-based variational multiscale (RBVMS) method and isogeometric analysis. The RBVMS formulation and its suitability and accuracy for turbulent flow in a moving domain are presented. Particular emphasis is placed on the parallel implementation of the methodology and its scalability. Two challenging flow cases were considered: the turbulent Taylor–Couette flow and the NREL 5 MW offshore baseline wind turbine rotor at full scale. In both cases, flow quantities of interest from the simulation results compare favorably with the reference …


Performance Analysis Of Solar Walls In Minnesota: Final Project Report, Patrick A. Tebbe, Saeed Moaveni, Louis Schwartzkopf Sep 2011

Performance Analysis Of Solar Walls In Minnesota: Final Project Report, Patrick A. Tebbe, Saeed Moaveni, Louis Schwartzkopf

Mechanical and Civil Engineering Department Publications

A study of unglazed transpired solar collectors (referred to as solar walls for this report), has been undertaken. Several installations in the Twin Cities, MN region have been identified, researched, and studied. A combination of weather stations, data logging systems, and building energy management systems were used to collect experimental data on four buildings. Performance calculations were then performed for these buildings and compared with various performance/modeling tools.


Evaluation Of Cathode Materials For Low Temperature (500-700c) Solid Oxide Fuel Cells, Alexander M. Lassman Sep 2011

Evaluation Of Cathode Materials For Low Temperature (500-700c) Solid Oxide Fuel Cells, Alexander M. Lassman

Master's Theses

Solid oxide fuel cells (SOFC) have gained a great deal of interest, due to their potential for high efficiency power generation and ability to utilize hydrogen fuel, as well as various hydrocarbon-based fuels. A recent trend in SOFC development has been towards lower operating temperatures (500-700°C), which can substantially reduce the cost and complexity of the system. This thesis presents an investigation into state of the art Ba- and La- based cathode materials for use in low temperature (500-700°C) solid oxide fuel cells.

Synthesis of A-site deficient [A=0.97] Ba0.5Sr0.5Co0.8Fe0.2O3 (BSCF) was …


2011 Fall Engr333 Project Assignment, Matthew K. Heun Sep 2011

2011 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2011 ENGR333 project focused on the Bunker Interpretive Center (BIC) at Calvin University.

I asked the students “What would it take for Calvin College to obtain an Energy Star rating for the BIC? Or, if the BIC already qualifies for an Energy Star rating, what would it take to improve the energy efficiency of the BIC (as measured by Energy Star metrics) by 15%, thereby ensuring Energy Star performance of the building into the future?”

Customer

As I recall, the customer for this project was Biology faculty member Randy Van Dragt.


Experimental And Numerical Investigations Of Tubular-Shaped Direct Methanol Fuel Cells (Dmfcs), Travis R. Ward Aug 2011

Experimental And Numerical Investigations Of Tubular-Shaped Direct Methanol Fuel Cells (Dmfcs), Travis R. Ward

Master's Theses

This study focuses on both the numerical and experimental investigations of the novel, passively operated, tubular-shaped, Direct Methanol Fuel Cell (DMFC) as an alternative geometry to the traditional planar-shaped fuel cell. The benefit of the tubular geometry compared to the planar geometry is the higher instantaneous volumetric power density provided by the larger active area, which could be beneficial in applications that require a high instantaneous power while occupying a small volume. First, a two-dimensional, two-phase, non-isothermal model was developed to investigate the steady-state performance and design characteristics of a tubular-shaped, passive DMFC. It was found that a higher ambient …


In Situ Synthesis Of Ultrafine Ss-Mno2/Polypyrrole Nanorod Composites For High-Performance Supercapacitors, Jianfeng Zang, Xiaodong Li Aug 2011

In Situ Synthesis Of Ultrafine Ss-Mno2/Polypyrrole Nanorod Composites For High-Performance Supercapacitors, Jianfeng Zang, Xiaodong Li

Faculty Publications

We report a remarkable observation that is at odds with the established notion that β-MnO2 was regarded as an undesirable candidate for supercapacitor applications. The specific capacitance of β-MnO2 can reach as high as 294 F g−1, which is comparable to the best crystallographic structure, like α-MnO2. The key is to substantially decrease the size of β-MnO2 powders to ultra small regime. We demonstrate a facile, simple, and effective approach to synthesizing ultrafine (<10 nm in diameter) β-MnO2/polypyrrole nanorod composite powders for high-performance supercapacitor electrodes. Our observation may encourage a revisit of the other good …


Characteristics Of The Hydrogen Electrode In High Temperature Steam Electrolysis Process, Chao Jin, Chenghao Yang, Fanglin Chen Aug 2011

Characteristics Of The Hydrogen Electrode In High Temperature Steam Electrolysis Process, Chao Jin, Chenghao Yang, Fanglin Chen

Faculty Publications

YSZ-electrolyte supported solid oxide electrolyzer cells (SOECs) using LSM-YSZ oxygen electrode but with three types of hydrogen electrode, Ni–SDC, Ni–YSZ and LSCM–YSZ have been fabricated and characterized under different steam contents in the feeding gas at 850°C. Electrochemical impedance spectra results show that cell resistances increase with the increase in steam concentrations under both open circuit voltage and electrolysis conditions, suggesting that electrolysis reaction becomes more difficult in high steam content. Pt reference electrode was applied to evaluate the contributions of the hydrogen electrode and oxygen electrode in the electrolysis process. Electrochemical impedance spectra and over potential of both electrodes …


The Explosion In Mari, Cyprus, The Cost Of Power Shortages, And Policy Recommendations, Theodoros Zachariadis, Panos Pashardes, Nicoletta Pashourtidou Aug 2011

The Explosion In Mari, Cyprus, The Cost Of Power Shortages, And Policy Recommendations, Theodoros Zachariadis, Panos Pashardes, Nicoletta Pashourtidou

Theodoros Zachariadis

No abstract provided.


Desalination Powered By Entropy, Sanza Kazadi, Young Hong, Calvin Chau, Apoorv Chaudhary, Arnav Chaudhary, James Park, Jessica Liu, Miji Kim, David Kim, Sam Kim Jul 2011

Desalination Powered By Entropy, Sanza Kazadi, Young Hong, Calvin Chau, Apoorv Chaudhary, Arnav Chaudhary, James Park, Jessica Liu, Miji Kim, David Kim, Sam Kim

Sanza Kazadi

We describe in this paper a novel water distiller. The water distiller utilizes a thermal gradient device which spontaneously generates and maintains a thermal gradient through a process similar to osmosis. A theoretical derivation of the process which we call an entrochemical process is presented. The device utilizes the thermal
gradient to induce a flow of energy through the system. This flow of energy is used to induce the distillation of water. The device may be recharged using a low-temperature evaporation process. We describe the
design of the device, which has a distillation process that has an efficiency of 12.6 …


Thermal Conductivity Reduction Through Isotope Substitution In Nanomaterials: Predictions From An Analytical Classical Model And Nonequilibrium Molecular Dynamics Simulations, Ganesh Balasubramanian, Ishwar K. Puri, Michael C. Bohm, Frederic Leroy Jul 2011

Thermal Conductivity Reduction Through Isotope Substitution In Nanomaterials: Predictions From An Analytical Classical Model And Nonequilibrium Molecular Dynamics Simulations, Ganesh Balasubramanian, Ishwar K. Puri, Michael C. Bohm, Frederic Leroy

Ganesh Balasubramanian

We introduce an analytical model to rapidly determine the thermal conductivity reduction due to mass disorder in nanomaterials. Although this simplified classical model depends only on the masses of the different atoms, it adequately describes the changes in thermal transport as the concentrations of these atoms vary. Its predictions compare satisfactorily with nonequilibrium molecular dynamics simulations of the thermal conductivity of 14C–12C carbon nanotubes as well as with previous simulations of other materials. We present it as a simple tool to quantitatively estimate the thermal conductivity decrease that is induced by isotope substitution in various materials.


Heat Conduction Across A Solid-Solid Interface: Understanding Nanoscale Interfacial Effects On Thermal Resistance, Ganesh Balasubramanian, Ishwar K. Puri Jul 2011

Heat Conduction Across A Solid-Solid Interface: Understanding Nanoscale Interfacial Effects On Thermal Resistance, Ganesh Balasubramanian, Ishwar K. Puri

Ganesh Balasubramanian

Phonons scatter and travel ballistically in systems smaller than the phonon mean free path. At larger lengths, the transport is instead predominantly diffusive. We employ molecular dynamics simulations to describe the length dependence of the thermal conductivity. The simulations show that the interfacial thermal resistance Rk for a Si-Ge superlattice is inversely proportional to its length, but reaches a constant value as the system dimension becomes larger than the phonon mean free path. This nanoscale effect is incorporated into an accurate continuum model by treating the interface as a distinct material with an effective thermal resistance equal to Rk .


Florida Solar Atlas, Florida Solar Energy Center, Charles Cromer Jul 2011

Florida Solar Atlas, Florida Solar Energy Center, Charles Cromer

FSEC Energy Research Center®

The direct beam and direct global solar resource values for any geographical location in Florida were found by using actual data taken at the Florida Solar Energy Center (FSEC) for 2010 and correlating those values against clearness values derived from NOAA geostationary satellite data. Using the correlations developed, eleven years of satellite data (2000 - 2010) were used to provide expected monthly average solar resource values for any location in Florida. These values as provided in watts per meter square per day, were matched to colors with the lowest values of the full range of average values representing the deepest …


Effect Of Climate Variability And Climate Change On Crop Production And Water Resources In Cyprus, Adriana Bruggeman, Christos Zoumides, Stelios Pashiardis, Panos Hadjinicolaou, Manfred Lange, Theodoros Zachariadis Jul 2011

Effect Of Climate Variability And Climate Change On Crop Production And Water Resources In Cyprus, Adriana Bruggeman, Christos Zoumides, Stelios Pashiardis, Panos Hadjinicolaou, Manfred Lange, Theodoros Zachariadis

Theodoros Zachariadis

No abstract provided.