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Full-Text Articles in Mechanical Engineering

Measuring Progress With Normalized Energy Intensity, Nathan Lammers, J. Kelly Kissock, Brian Abels, Franc Server Apr 2011

Measuring Progress With Normalized Energy Intensity, Nathan Lammers, J. Kelly Kissock, Brian Abels, Franc Server

Mechanical and Aerospace Engineering Faculty Publications

Energy standard ISO 50001 will require industries to quantify improvement in energy intensity to qualify for certification. This paper describes a four-step method to analyze utility billing, weather, and production data to quantify a company's normalized energy intensity over time. The method uses 3-pararameter change-point regression modeling of utility billing data against weather and production data to derive energy signature equations. The energy signature equation is driven by typical weather and production data to calculate the 'normal annual consumption', NAC, and divided by typical production to calculate 'normalized energy intensity' NEI. These steps are repeated on sequential sets of 12 …


Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock Apr 2011

Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

Compressed air storage is an important, but often misunderstood, component of compressed air systems. This paper discusses methods to properly size compressed air storage in load-unload systems to avoid short cycling and reduce system energy use. First, key equations relating storage, pressure, and compressed air flow are derived using fundamental thermodynamic relations. Next, these relations are used to calculate the relation between volume of storage and cycle time in load-unload compressors. It is shown that cycle time is minimized when compressed air demand is 50% of compressor capacity. The effect of pressure drop between compressor system and storage on cycle …


Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock Apr 2011

Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

The automotive industry is the largest industry in the United States in terms of the dollar value of production [1]. U.S. automakers face tremendous pressure from foreign competitors, which have an increasing manufacturing presence in this country. The Big Three North American Original Equipment Manufacturers (OEMs)-General Motors, Ford, and Chrysler-are reacting to declining sales figures and economic strain by working more efficiently and seeking out opportunities to reduce production costs without negatively affecting the production volume or the quality of the product. Successful, cost-effective investment and implementation of the energy efficiency technologies and practices meet the challenge of maintaining the …


Wind Energy Potential For Reverse Osmosis Desalination Plants In La Guajira, Colombia, Carlos Martinez-Smit Jan 2011

Wind Energy Potential For Reverse Osmosis Desalination Plants In La Guajira, Colombia, Carlos Martinez-Smit

Faculty-Selected Student Works

Project report required by the Master of Science Degree in Renewable and Clean Energy.

Abstract:

The region of La Guajira, located in the north of Colombia, has a lot of potential for wind power with annual average wind speeds up to 11 m/s at 10 m height in some locations, according to the national wind map. Most of the wind potential is located in Upper Guajira, where 90% of the population is indigenous Wayuu people (among the country’s poorest population) and it is also characterized with low precipitation, 500 mm/yr, high evapotranspiration, 1500 mm/yr, and low humidity. All this creates …


Investigation On Flame Characteristics Of Oxy-Fuel Combustion, Md R. Islam Jan 2011

Investigation On Flame Characteristics Of Oxy-Fuel Combustion, Md R. Islam

Open Access Theses & Dissertations

Oxy-fuel combustion is currently being considered by the U.S Department of Energy as a promising technology for efficient carbon capture. This technology could substantially reduce NOx and CO2 emissions. In addition, the implementation of oxy-fuel combustion technology in a power generation system could potentially reduce negative environmental impacts of fossil fuel use. It also encourages the use of reliable and domestic energy sources. The U.S. Department of Energy has made efforts to investigate the performance of a CO2 and H2O diluted oxy-fuel combustion system in a high-pressure combustor. In an effort to better understand and characterize the fundamental flame characteristics …


Experimental And Numerical Investigation Of The Effect Of Fuel Composition On Flame Stability On A Gas Turbine Combustor, Gilberto Corona Jan 2011

Experimental And Numerical Investigation Of The Effect Of Fuel Composition On Flame Stability On A Gas Turbine Combustor, Gilberto Corona

Open Access Theses & Dissertations

Gas turbines are used for power generation and aviation all over the world. Fossil fuels remain the main source of energy for the operation of gas turbines but the recent increase in environmental awareness has influenced government agencies to impose stringent limits on pollutant emissions from power generation plants. Pollutant emissions control is one of the major challenges for gas turbine designers. In this study, experimental methods and computational fluid dynamics (CFD) technologies are used to study the problems that arise when coal derived fuels are used in Gas Turbine Combustors.

Gas turbine designers need both experimental data and combustion …


2010 Fall Engr333 Project Final Report, 2010 Fall Engr333 Dec 2010

2010 Fall Engr333 Project Final Report, 2010 Fall Engr333

ENGR 333

Calvin College dorms have a chronic issue with wasting energy. The dorms have little insulation, high infiltration rates, and are heated by low efficiency boilers. These existing characteristics combine for a larger required heating load and increased energy usage. The excess heat, due to poor temperature control, is often vented out through the windows whenever students deem necessary. This project will attempt to reduce wasted energy and efficiently distribute heat as needed.

The Thermal Systems Design class of 2010 was challenged with retrofitting the Bolt-Heyns-Timmer (BHT) dorm to decrease energy consumption and improve efficiency. The class was presented with the …


College Of Engineering Senior Design Competition Fall 2010, University Of Nevada, Las Vegas Dec 2010

College Of Engineering Senior Design Competition Fall 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …


Agenda: 2010 World Energy Justice Conference: Emerging Solutions For The Energy Poor: Technological, Entrepreneurial And Institutional Challenges, University Of Colorado Boulder. Center For Energy & Environmental Security, Colorado Journal Of International Environmental Law And Policy Nov 2010

Agenda: 2010 World Energy Justice Conference: Emerging Solutions For The Energy Poor: Technological, Entrepreneurial And Institutional Challenges, University Of Colorado Boulder. Center For Energy & Environmental Security, Colorado Journal Of International Environmental Law And Policy

2010 World Energy Justice Conference (November 5)

This conference is a sequel to the 2009 World Energy Justice Conference (WEJC 2009) which began examining ways of mainstreaming safe, clean, and efficient energy for the world's Energy Poor (EP). The EP number two and a half billion people living on less than $1-2 a day who have no access to modern energy services. WEJC 2010 more fully develops these themes. WEJC 2010 will explore how the next round of global warming meetings in Cancun could design new flexibility mechanisms that give credits, for example, for the reduction of black carbon by the adoption of cookstoves, and embrace small …


Impact Investigation Of Reactor Fuel Operating Parameters On Reactivity For Use In Burnup Credit Applications, Tanya N. Sloma Nov 2010

Impact Investigation Of Reactor Fuel Operating Parameters On Reactivity For Use In Burnup Credit Applications, Tanya N. Sloma

UNLV Theses, Dissertations, Professional Papers, and Capstones

When representing the behavior of commercial spent nuclear fuel (SNF), credit is sought for the reduced reactivity associated with the net depletion of fissile isotopes and the creation of neutron-absorbing isotopes, a process that begins when a commercial nuclear reactor is first operated at power. Burnup credit accounts for the reduced reactivity potential of a fuel assembly and varies with the fuel burnup, cooling time, and the initial enrichment of fissile material in the fuel. With regard to long-term SNF disposal and transportation, tremendous benefits, such as increased capacity, flexibility of design and system operations, and reduced overall costs, provide …


2010 Fall Engr333 Project Assignment, Matthew K. Heun Sep 2010

2010 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2010 ENGR333 project focused on heating and air-conditioning in campus dormitories, which are notoriously leaky and inefficient.

I asked the students “What would it take to retrofit the Bolt-Heyns-Timmer (BHT) dormitory heating and air-conditioning systems in a manner that achieves LEED certification?”

Customer

The customer for this project was Calvin’s VP for finance Henry DeVries.


User's Guide To Mbc3: Multi-Blade Coordinate Transformation Code For 3-Bladed Wind Turbine, G. S. Bir Sep 2010

User's Guide To Mbc3: Multi-Blade Coordinate Transformation Code For 3-Bladed Wind Turbine, G. S. Bir

Publications (E)

The dynamics of wind turbine rotor blades are conventionally expressed in rotating frames attached to the individual blades. The tower-nacelle subsystem though, sees the combined effect of all rotor blades, not the individual blades. Also, the rotor responds as a whole to excitations such as aerodynamic gusts, control inputs, and tower-nacelle motion—all of which occur in a nonrotating frame. Multi-blade coordinate transformation (MBC) helps integrate the dynamics of individual blades and express them in a fixed (nonrotating) frame. MBC involves two steps: transforming the rotating degrees of freedom and transforming the equations of motion. Reference 1 details the MBC operation. …


Wind Flow Modeling For Wind Energy Analysis Of The Nellis Dunes Area In Nevada, Upendra Rangegowda Aug 2010

Wind Flow Modeling For Wind Energy Analysis Of The Nellis Dunes Area In Nevada, Upendra Rangegowda

UNLV Theses, Dissertations, Professional Papers, and Capstones

A wind energy analysis of the Nellis Dunes area in Nevada was conducted. A DEM file which contains the elevation data was used to generate the surface model and to create a 3-D mesh of the region. Local meteorological tower data collected for a period of one year was used to generate the diagnostic initial wind fields. Upper level wind fields were created using a surface boundary layer technique along with linear interpolation of the tower level wind fields. The vertical components of the velocities were adjusted using the equation of continuity. Mass consistent 3-D wind fields were then calculated …


The Applications And Limitations Of Printable Batteries, Matthew Delmanowski Jun 2010

The Applications And Limitations Of Printable Batteries, Matthew Delmanowski

Graphic Communication

This study focuses on the potential applications for printed batteries and how they could affect the printing industry. It also analyzes the main problems associated with manufacturing this technology and what needs to be done to overcome these issues. To find the answers to these questions, two methods of research were used. The first was through the elite and specialized interviewing of Dr. Scott Williams of Rochester Institute of Technology and Professor Nancy Cullins from Cal Poly. The second form of research was a common, yet useful, method called secondary research. This entailed looking at recent written research papers about …


Hydrogen Separation Membranes, University Of North Dakota. Energy And Environmental Research Center May 2010

Hydrogen Separation Membranes, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Technical brief describing hydrogen separation membranes and their potential to reduce cost of hydrogen production and CO2 separation. Outlines membrane types, commercially available membranes, and new technological developments. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


College Of Engineering Senior Design Competition Spring 2010, University Of Nevada, Las Vegas Apr 2010

College Of Engineering Senior Design Competition Spring 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Each student in his or her senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. The senior design project encourages the student to use everything learned in the engineering program to create a practical, real-world solution to an engineering challenge.

A highlight of the year-long senior design project is the senior design competition. This competition, which usually takes place the week before finals each semester, helps focus the senior students on increasing the quality and potential for commercial application for their design projects.

Judges from local industry evaluate the projects on innovation, commercial …


Solar Power And The Electric Grid, Energy Analysis, Nrel Energy Analysis Mar 2010

Solar Power And The Electric Grid, Energy Analysis, Nrel Energy Analysis

Publications (E)

In today’s electricity generation system, different resources make different contributions to the electricity grid. This fact sheet illustrates the roles of distributed and centralized renewable energy technologies, particularly solar power, and how they will contribute to the future electricity system. The advantages of a diversified mix of power generation systems are highlighted.


Climate And More Sustainable Cities: Climate Information For Improved Planning And Management Of Cities (Producers/Capabilities Perspective), C.S.B. Grimmond, Matthias Roth, Tim R. Oke, Y. C. Au, M. Best, R. Betts, Gregory R. Carmichael, Helen Cleugh, Walter F. Dabberdt, Rohinton Emmanuel, E. Freitas, K. Fortuniak, Steven Hanna, Petra M. Klein, Laurence S. Kalkstein, C. H. Liu, Alex Nickson, David Pearlmutter, David J. Sailor, James Voogt Jan 2010

Climate And More Sustainable Cities: Climate Information For Improved Planning And Management Of Cities (Producers/Capabilities Perspective), C.S.B. Grimmond, Matthias Roth, Tim R. Oke, Y. C. Au, M. Best, R. Betts, Gregory R. Carmichael, Helen Cleugh, Walter F. Dabberdt, Rohinton Emmanuel, E. Freitas, K. Fortuniak, Steven Hanna, Petra M. Klein, Laurence S. Kalkstein, C. H. Liu, Alex Nickson, David Pearlmutter, David J. Sailor, James Voogt

Mechanical and Materials Engineering Faculty Publications and Presentations

In the last two decades substantial advances have been made in the understanding of the scientific basis of urban climates. These are reviewed here with attention to sustainability of cities, applications that use climate information, and scientific understanding in relation to measurements and modelling. Consideration is given from street (micro) scale to neighbourhood (local) to city and region (meso) scale. Those areas where improvements are needed in the next decade to ensure more sustainable cities are identified. High-priority recommendations are made in the following six strategic areas: observations, data, understanding, modelling, tools and education. These include the need for more …


Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory Jan 2010

Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory

Publications (E)

The National Renewable Energy Laboratory (NREL) is the nation’s primary laboratory for renewable energy and energy efficiency research and development.

NREL’s mission and strategy are focused on advancing the U.S. Department of Energy’s and our nation’s energy goals. The laboratory’s scientists and researchers support critical market objectives to accelerate research from scientific innovations to market-viable alternative energy solutions. At the core of this strategic direction are NREL’s research and technology development competencies. These areas span from understanding renewable resources for energy, to the conversion of these resources to renewable electricity and fuels, and ultimately to the use of renewable electricity …


College Of Engineering Senior Design Competition Fall 2009, University Of Nevada, Las Vegas Dec 2009

College Of Engineering Senior Design Competition Fall 2009, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Each student in his or her senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. The senior design project encourages the student to use everything learned in the engineering program to create a practical, real-world solution to an engineering challenge.

A highlight of the year-long senior design project is the senior design competition. This competition, which usually takes place the week before finals each semester, helps focus the senior students on increasing the quality and potential for commercial application for their design projects.

Judges from local industry evaluate the projects on innovation, commercial …


National Center For Hydrogen Technology, University Of North Dakota. Energy And Environmental Research Center Oct 2009

National Center For Hydrogen Technology, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Brochure about the Energy & Environmental Research Center's National Center for Hydrogen Technology. Includes its role in developing technologies that produce and utilize hydrogen. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]


The Very Basics Of Sustainability - An Alternative Viewpoint, Jim Mcgovern Aug 2009

The Very Basics Of Sustainability - An Alternative Viewpoint, Jim Mcgovern

Other resources

This paper examines the context and meaning of the term ‘sustainability’, the factors that determine and govern climate on Earth, the population of the Earth and its trends and influencers, the requirements for sustaining life and the options that are available to humankind. Some viewpoints are presented that are alternative to ‘conventional alternative’ thinking. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’ and also argues that humankind needs to face …


The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern Aug 2009

The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern

Other resources

This presentation sets out the very basics of ‘sustainability’, although a definition of sustainability is not attempted. Some of the very basics are the context in which the Earth and humankind exist in space and time, the Earth’s climate, the Earth’s population and humankind’s options and choices. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’. The author also argues that, in addressing the challenges that humankind faces, globally concerted effort …


College Of Engineering Senior Design Competition Spring 2009, University Of Nevada, Las Vegas May 2009

College Of Engineering Senior Design Competition Spring 2009, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …


An Experimental Study Of The Hydrodynamics Of Multiphase Flow In Fluidized Beds, Gerardo Vargas Jan 2009

An Experimental Study Of The Hydrodynamics Of Multiphase Flow In Fluidized Beds, Gerardo Vargas

Open Access Theses & Dissertations

Fluidized bed reactors have been widely used as a gasifier in coal gasification processes to convert coal into other forms of energy. At this stage, full fluidization is required to attain the best thermochemical reaction within the fluid-solid mixture. This can only be achieved if the fluid is maintained between minimum fluidization and terminal velocities. To better understand the hydrodynamics of multiphase flow, a fluidized bed was designed and constructed to carry out the investigation. Compressed air and 1-mm glass beads were used to determine gas minimum fluidization and terminal velocities at three different particle concentrations. The solids were enclosed …


Parametric Study Of Efficiency Measures For Home Energy Conservation In Las Vegas, Nevada, Todd M. France Jan 2009

Parametric Study Of Efficiency Measures For Home Energy Conservation In Las Vegas, Nevada, Todd M. France

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pulte Homes, a production home builder and community developer partnering with the U.S. Department of Energy's Building America program, has collaborated with the Center for Energy Research at the University of Nevada, Las Vegas and NV Energy, the local electric utility, on an energy conservation project in the Las Vegas Valley.

This study entails four model homes at a new development in the Summerlin community of Las Vegas, Nevada, named Villa Trieste. The home models, ranging in floor plan area from 1,487 to 1,777 square feet, have been constructed under the Environments for Living program and are LEED (Leadership in …


Optimization Of Solid Oxide Fuel Cell Interconnect Design, Krishna C. Pulagam Jan 2009

Optimization Of Solid Oxide Fuel Cell Interconnect Design, Krishna C. Pulagam

UNLV Theses, Dissertations, Professional Papers, and Capstones

Performance of solid oxide fuel cells (SOFC) is dependent of a set of complex physical and chemical processes occurring simultaneously. Interconnect for SOFC is important as it provides electrical connection between anode of one individual cell to the cathode of neighboring one. It also acts as a physical barrier to protect the air electrode material from the reducing environment of the fuel on the fuel electrode side, and it equally prevents the fuel electrode material from contacting with oxidizing atmosphere of the oxidant electrode side. A three-dimensional numerical model has been developed to evaluate the SOFC including the current collector, …


Empirically Derived Formulas To Predict Indoor Maximum, Average, And Minimum Temperatures In Roofpond Buildings Using Minimum Climatic Information, Ibrahim Kivarkis Kako Jan 2009

Empirically Derived Formulas To Predict Indoor Maximum, Average, And Minimum Temperatures In Roofpond Buildings Using Minimum Climatic Information, Ibrahim Kivarkis Kako

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis introduces an empirically developed formula to predict the comfort conditions and thermal performance of a Skytherm(TM) Southwest Roofpond placed over a light-weight un-insulated structure built at the School of Architecture at the University of Nevada, Las Vegas.

The predictive formula introduced in this study may be used in different parts of the world (particularly developing nations where insulation and air-conditioning are rarely used) to predict the performance of a Skytherm(TM) Southwest Roofpond using minimal climate data.

The data collected in the experimental setup at the Natural Energies Advanced Technologies Laboratory included outside and inside temperatures of various surfaces …


Two-Tank Indirect Thermal Storage Designs For Solar Parabolic Trough Power Plants, Joseph E. Kopp Jan 2009

Two-Tank Indirect Thermal Storage Designs For Solar Parabolic Trough Power Plants, Joseph E. Kopp

UNLV Theses, Dissertations, Professional Papers, and Capstones

The performance of a solar thermal parabolic trough plant with thermal storage is dependent upon the arrangement of the heat exchangers that ultimately transfer energy from the sun into steam. The steam is utilized in a traditional Rankine cycle power plant. The most commercially accepted thermal storage design is an indirect two-tank molten salt storage system where molten salt interacts with the solar field heat transfer fluid (HTF) through a heat exchanger. The molten salt remains in a closed loop with the HTF and the HTF is the heat source for steam generation. An alternate indirect two tank molten salt …


Optimization Of Channel Geometry In A Proton Exchange Membrane (Pem) Fuel Cell, Jephanya Kasukurthi Jan 2009

Optimization Of Channel Geometry In A Proton Exchange Membrane (Pem) Fuel Cell, Jephanya Kasukurthi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Bipolar plates are the important components of the PEM fuel cell. The flow distribution inside the bipolar plate should be uniform. Non-uniform flow distribution inside the bipolar leads to poor performance of the fuel cell and wastage of expensive catalyst. A single channel PEM fuel cell is taken and electrochemical analysis is carried out on it. The results are compared with the available published experimental data obtained by other research group, and they are found to be in good agreement. A baseline design of the bipolar plate is taken and numerical analysis is carried out. The results show that the …