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Full-Text Articles in Engineering

Multiscale Investigation Of Dropwise Condensation On A Smooth Hydrophilic Surface, Shahab Bayani Ahangar Jan 2021

Multiscale Investigation Of Dropwise Condensation On A Smooth Hydrophilic Surface, Shahab Bayani Ahangar

Dissertations, Master's Theses and Master's Reports

The objective of this work is to identify the fundamental mechanism of dropwise condensation on a smooth solid surface by probing the solid-vapor interface during phase-change to evaluate the existence and structure of the thin film and the initial nucleus that develop during condensation. In this work, an automated Surface Plasmon Resonance imaging (SPRi) instrument with the ability to perform imaging in intensity modulation and angular modulation is developed. The SPRi instrument is used to probe (in three dimensions) the adsorbed film that forms on the substrate during dropwise condensation. SPRi with a lateral resolution of ~ 4-10 μm, thickness …


Marangoni Propulsion Of Active Particles, Saeed Jafari Kang Jan 2021

Marangoni Propulsion Of Active Particles, Saeed Jafari Kang

Dissertations, Master's Theses and Master's Reports

We study the surfing motion of active particles located at a flat liquid-gas interface. The particles create and maintain a surface tension gradient by asymmetrically discharging a surface tension-reducing agent. We employ theory and numerical simulation to investigate the Marangoni propulsion of these active surfers. First, we use the reciprocal theorem to establish a relationship between the propulsion speed and the release of the active chemical. This theoretical relation is utilized to examine the effect of wall confinement and geometry on the Marangoni-driven motion of active particle when the inertial effects are negligible and when the transports of the released …


Test 2231: John Deere 8r 250, Nebraska Tractor Test Lab Jan 2021

Test 2231: John Deere 8r 250, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 2084a: John Deere 7r 270, Nebraska Tractor Test Lab Jan 2021

Test 2084a: John Deere 7r 270, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Hydraulic Vehicle Challenge, Jacob Steiner, David Kotovets, Evan Blitz, Luke Fetherston, Alex Colucy Jan 2021

Hydraulic Vehicle Challenge, Jacob Steiner, David Kotovets, Evan Blitz, Luke Fetherston, Alex Colucy

Williams Honors College, Honors Research Projects

The target goal of this project is for a team of students to design a vehicle which is based on human power as the primary mover of the system and achieves vehicle propulsion through the required use of hydraulics and pneumatics. In summary, the rider will power a pump that will generate pressure in order to move the fluid that drives the motor. This will result in the powered rotation of the wheels. As there are many possible designs, naturally, this means that the final design for the vehicle will have specific limitations such as weight and the required use …


An Equest Based Building Energy Modeling Analysis For Energy Efficiency Of Buildings, Saroj Lamichhane Jan 2021

An Equest Based Building Energy Modeling Analysis For Energy Efficiency Of Buildings, Saroj Lamichhane

Graduate Theses, Dissertations, and Problem Reports (ETD)

Building energy performance is a function of numerous building parameters. In this study, sensitivity analysis on twenty parameters is performed to determine the top three parameters which have the most significant impact on the energy performance of buildings. Actual data from two fully operational commercial buildings were collected and used to develop a building energy model in eQUEST. The model is calibrated using Normalized Mean Bias Error (NMBE) and Coefficient of Variation of Root Mean Square Error (CV(RMSE)) method. The model satisfies the NMBE and CV(RMSE) criteria set by the American Society of Heating, Refrigeration, and Air-Conditioning (ASHRAE) Guideline 14, …


Determination Of Effectiveness Of Energy Management System In Buildings, Vivash Karki Jan 2021

Determination Of Effectiveness Of Energy Management System In Buildings, Vivash Karki

Graduate Theses, Dissertations, and Problem Reports (ETD)

Building Energy Management Systems (BEMS) are computer-based systems that aid in managing, controlling, and monitoring the building technical services and energy consumption by equipment used in the building. The effectiveness of BEMS is dependent upon numerous factors, among which the operational characteristics of the building and the BEMS control parameters also play an essential role. This research develops a user-driven simulation tool where users can input the building parameters and BEMS controls to determine the effectiveness of their BEMS. The simulation tool gives the user the flexibility to understand the potential energy savings by employing specific BEMS control and help …


On The Improvement Of The Indirect Quantification Of Methane Emissions: A Stationary Single Sensor Approach, Robert Scott Heltzel Jan 2021

On The Improvement Of The Indirect Quantification Of Methane Emissions: A Stationary Single Sensor Approach, Robert Scott Heltzel

Graduate Theses, Dissertations, and Problem Reports (ETD)

There is a need for improved indirect quantification of methane emissions, particularly from the natural gas industry. Natural gas production continues to increase along with the number of wells and production sites. These production sites have the potential to contribute significant levels of methane emissions. Methane is a potent greenhouse gas and the primary component of natural gas. A more complete understanding of emissions through improved quantification will lead to enhanced mitigation. Emissions have historically been quantified with both direct and indirect methods, with varying results. Emissions have been shown to be both temporally and spatially variable. These facts have …


Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini Jan 2021

Improving Real-Time Methane Monitoring In Longwall Coal Mines Through System Response Characterization Of A Multi-Nodal Methane Detection Network, Brian Philip Cappellini

Graduate Theses, Dissertations, and Problem Reports (ETD)

Machine automation and atmospheric monitoring are used by many industries to improve safety and productivity in the workplace. The underground Methane Watchdog System (MWS) is a multi-nodal network of sensors currently under development. The MWS aims to improve safety and productivity by introducing 10 compact sampling units designed to be easily integrated within the current roof support equipment of the mine. Each unit contains an array of sensors used to continuously monitor the environmental conditions which include methane concentration, temperature, pressure, and relative humidity. All MWS units report information back to a remote central processing hub (CPH) which collects nodal …


Performance And Economical Analysis Of Different Insulating Materials Used To Reduce The Heat Load Of An Existing Residential Building, Radwa A. El-Awadly, Ahmed A. Abdel-Rehim Jan 2021

Performance And Economical Analysis Of Different Insulating Materials Used To Reduce The Heat Load Of An Existing Residential Building, Radwa A. El-Awadly, Ahmed A. Abdel-Rehim

Mechanical Engineering

The energy consumption from the residential sector is an important element which has an impact on the total energy consumption in any country. The heating and air conditioning loads can be reduced through many means. Using thermal insulation in buildings does not only contribute in reducing the required air conditioning system size, but also in reducing the annual energy cost for the whole building. In this case, the energy saving varies according to the building type, the climatic conditions at which the building is located as well as the type of the insulating material used. In the present study, an …


Effect Of Dust And High Temperature On Photovoltaics Performance In The New Capital Area, Engy Elshazly, Ahmed A. Abdel-Rehim, Amr Abdel Kader, Iman El-Mahallawi Jan 2021

Effect Of Dust And High Temperature On Photovoltaics Performance In The New Capital Area, Engy Elshazly, Ahmed A. Abdel-Rehim, Amr Abdel Kader, Iman El-Mahallawi

Mechanical Engineering

The trend for integrating solar Photovoltaic Panels as an alternative renewable and sustainable energy source is growing in Egypt, North Africa and the Middle East. However, these efforts are not widely accepted by the society due to their lower efficiencies. The efficiency of the photovoltaic panels is affected by many environmental parameters, which have a negative impact on system efficiency and cost of energy, dust and increased panel temperatures being the most serious. This work presents the results of a case study conducted at The British University in Egypt at El-Sherouk city to study the effect of different parameters such …


An Experimental Study Of A Hemi-Spherical Solar Collector Under Egyptian Climate, Mohamed Ebaid, Salma Salah, Ahmed A. Abdel-Rehim Jan 2021

An Experimental Study Of A Hemi-Spherical Solar Collector Under Egyptian Climate, Mohamed Ebaid, Salma Salah, Ahmed A. Abdel-Rehim

Mechanical Engineering

Traditional flat plate collectors have shown, under many investigations, low system operating efficiency, which prompted the idea of designing new solar collectors operating with higher efficiency. Such designs include spherical, hemi-spherical, cylindrical, or rhombic solar collectors. The current study experimentally investigates the performance of a stationary newly designed hemi-spherical solar collector in comparison with a flat plate solar collector with the same surface area and weather conditions. This target has been achieved through designing and manufacturing a hemi-spherical collector, followed by analyzing its performance under normal operating conditions of Egyptian climate. The Hemi-spherical solar collector showed a maximum efficiency of …


Energy And Exergy Analysis For Stationary Solar Collectors Using Nanofluids: A Review, Mahmoud Eltaweel, Ahmed A. Abdel-Rehim Jan 2021

Energy And Exergy Analysis For Stationary Solar Collectors Using Nanofluids: A Review, Mahmoud Eltaweel, Ahmed A. Abdel-Rehim

Mechanical Engineering

Fossil fuels demonstrate pollution effects and significant emissions on the atmosphere, which made the use of clean, renewable sources of energy a necessity. Renewable energy has many sources, but the most promising and cheapest energy source is solar energy, which has led to a focus on efficient solar energy harvesting to be cheaper for public use. Stationary solar collectors like evacuated tube and flat-plate solar collectors are the most commonly used solar collectors for their simplicity of installation and maintenance. They are mostly used for domestic applications such as solar water heaters. Nanofluids can improve the thermal properties of the …


Numerical Investigation Of The Thermal Performance Of An Axially Rotating Internally Finned Receiver Tube Of A Parabolic Trough Concentrator, Andrew S. Tanious,, Ahmed A. Abdel-Rehim Jan 2021

Numerical Investigation Of The Thermal Performance Of An Axially Rotating Internally Finned Receiver Tube Of A Parabolic Trough Concentrator, Andrew S. Tanious,, Ahmed A. Abdel-Rehim

Mechanical Engineering

Enhancement of the thermal performance of the parabolic trough receiver tube is one of the approaches to energy sustainability. In the present work, the thermal performance of an axially rotating receiver tube equipped with internal flat longitudinal fins is studied. The effects of both the fin height and the rate of axial rotation are investigated at low values of axial Reynold’s number. The numerical analysis is held at various rotation rates using ANSYS Fluent. The numerical findings showed that the effect of the axial rotation on the internally finned receiver tube is not significant yet negative where a maximum reduction …


Recent Advances In Preparation And Testing Methods Of Engine-Based Nanolubricants: A State-Of-The-Art Review, Sayed Akl, Sherif Elsoudy, Ahmed A. Abdel-Rehim, Serag Salem, Mark Ellis Jan 2021

Recent Advances In Preparation And Testing Methods Of Engine-Based Nanolubricants: A State-Of-The-Art Review, Sayed Akl, Sherif Elsoudy, Ahmed A. Abdel-Rehim, Serag Salem, Mark Ellis

Mechanical Engineering

Reducing power losses in engines is considered a key parameter of their efficiency improvement. Nanotechnology, as an interface technology, is considered one of the most promising strategies for this purpose. As a consumable liquid, researchers have studied nanolubricants through the last decade as potential engine oil. Nanolubricants were shown to cause a considerable reduction in the engine frictional and thermal losses, and fuel consumption as well. Despite that, numerous drawbacks regarding the quality of the processed nanolubricants were discerned. This includes the dispersion stability of these fluids and the lack of actual engine experiments. It has been shown that the …


A Comprehensive Comparative Investigation On Solar Heating And Cooling Technologies From A Thermo-Economic Viewpoint—A Dynamic Simulation, Hassan Jafari Mosleh, Pooria Behnam, Maryam Abbasi Kamazani, Omid Mohammadi, Soheil Kavian, Pouria Ahmadi, Marc A. Rosen Jan 2021

A Comprehensive Comparative Investigation On Solar Heating And Cooling Technologies From A Thermo-Economic Viewpoint—A Dynamic Simulation, Hassan Jafari Mosleh, Pooria Behnam, Maryam Abbasi Kamazani, Omid Mohammadi, Soheil Kavian, Pouria Ahmadi, Marc A. Rosen

Research outputs 2014 to 2021

© 2020 The Authors. Energy Science & Engineering published by the Society of Chemical Industry and John Wiley & Sons Ltd. The yearly thermo-economic performance is dynamically investigated for three solar heating and cooling systems: solar heating and absorption cooling (SHAC), solar heating and ejector cooling (SHEC), and heating and solar vapor compression cooling (HSVC). First, the effects of important design parameters on the thermo-economic performance of the systems to supply the heating and cooling loads of the building are evaluated. The systems are parametrically analyzed with the weather conditions of Tehran, Iran. The results show that the life cycle …


Fermentability Of Concentrated Sulfuric Acid Hydrolyzates From Aspenwood And Pinewood, Kando Janga Dec 2020

Fermentability Of Concentrated Sulfuric Acid Hydrolyzates From Aspenwood And Pinewood, Kando Janga

Tanzania Journal of Engineering and Technology (TJET)

The fermentability of hydrolyzates derived from two-stage concentrated sulfuric acid hydrolysis of Trembling aspen (Populus tremula) and Scots pine (Pinus sylvestris) were investigated. Three types of hydrolyzates were produced at mild, moderate and high decrystallization severity conditions. Portions of each of the original hydrolyzates were concentrated by vacuum evaporation to increase the sugar fraction to simulate industrial applications. Both sets of hydrolyzates were fermented anaerobically using Saccharomyces cerevisiae ATCC 96581. After 23 hours of fermentation, complete glucose consumption was observed for all the original hydrolyzates, with no signs of inhibition. The ethanol yields from these hydrolyzates ranged from 68% to …


Analysis Of Performance Characteristics Predicted From Several Experimental Data And Conversion Methods For Pumps As Turbine Application Using Statistical Techniques, Ombeni J. Mdee Dec 2020

Analysis Of Performance Characteristics Predicted From Several Experimental Data And Conversion Methods For Pumps As Turbine Application Using Statistical Techniques, Ombeni J. Mdee

Tanzania Journal of Engineering and Technology (TJET)

Different performance characteristics have been indicated when running centrifugal pumps in the reverse direction. The water flows from the discharge side of the pump to the suction side to run in the reverse direction and generate the mechanical rotational energy for the micro-hydropower plant. The current study evaluates the extent of variation of performance characteristics predicted by several experimental data from different pump-specific speeds and conversion methods. The performance characteristics discussed include the head, flow rate, efficiency and specific speed. The flow rate and head of a pump operating in pump mode divided with the characteristic of the pump operating …


Potential For Increased Rural Electrification Rate In Sub-Saharan Africa Using Swer Power Distribution Networks, Aviti Thadei Mushi Dec 2020

Potential For Increased Rural Electrification Rate In Sub-Saharan Africa Using Swer Power Distribution Networks, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

Rural electrification rate (RER) in Africa is still low to date. Several countries in Sub-Saharan Africa have tried to address this problem using conventional single phase two-wire or three-phase three-wire systems, however at large costs due to the nature of dispersed rural load centres, low load demand, and low population density. Another solution of off-grid generation creates associated health problems. Therefore, this paper undertakes a review of a single wire earth return (SWER) network as a RER improvement solution. The paper undertakes intensive literature review to elucidate challenges and solutions to the implementation of SWER technology. Advantages of SWER technology …


Wind Power Integration And Its Impact On Power Quality-A Didactic Approach, Santos Kihwele Dr Dec 2020

Wind Power Integration And Its Impact On Power Quality-A Didactic Approach, Santos Kihwele Dr

Tanzania Journal of Engineering and Technology (TJET)

This paper presents a model of a wind power system integrated with realistic power system, with intention of using it in addressing power quality issues in relations to grid codes during steady-state operation transient-state operation i.e., presence of grid fault events. For that case, a didactic approach of the normal performance of power systems due to the connection of fixed-speed wind turbine with induction generators is used. A study of integrating wind farms will be presented, including the incidence of high inrush current due to switching capacitor banks, out-rush current and voltage sags due to nearby three phase faults. As …


Solar Photovoltaic Performance Monitoring: A Bibliometric Review, Research Gaps And Opportunities, Javed Sayyad, Paresh Nasikkar Dec 2020

Solar Photovoltaic Performance Monitoring: A Bibliometric Review, Research Gaps And Opportunities, Javed Sayyad, Paresh Nasikkar

Library Philosophy and Practice (e-journal)

Electrical power generation has been revolutionized by growing demand and use of Renewable Energy (RE) sources such as Solar Photovoltaic (SPV) as the main electricity source in modern times. The main objective of this bibliometric analysis is to understand the scope of the literature available for SPV performance characterization. This detailed reviewed was performed on the documents related to SPV research considering all the subject categories from Scopus and Web of Science (WoS) databases. The patterns for the particular set of keywords were broke down with the recuperated outcomes from Scopus database in the language, publication type, year of publication, …


Florida Building Code, Energy Conservation, 7th Edition (2020) Vs. 2018 International Energy Conservation Code Residential Stringency Analysis, Florida Solar Energy Center, Jeffrey Sonne Dec 2020

Florida Building Code, Energy Conservation, 7th Edition (2020) Vs. 2018 International Energy Conservation Code Residential Stringency Analysis, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This report summarizes the review and evaluation activities carried out to make a determination whether the residential provisions of the 7th Edition (2020) Florida Building Code, Energy Conservation meet or exceed those of the 2018 International Energy Conservation Code (IECC) code.


Market Driven Residential Energy Codes: Comparing Performance In A Changing Technical Environment, Code Official Survey Results, Florida Solar Energy Center, Karen Fenaughty Dec 2020

Market Driven Residential Energy Codes: Comparing Performance In A Changing Technical Environment, Code Official Survey Results, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

The DOE Code Survey conducted for this project was launched on 2/18/2020 and closed 3/20/2020. There were 907 participants responding to at least some portion of the 48 question survey, though some questions received poor attention. Note that the number of responses to each question varies by design and depends on answers to prior questions. Further, multiple answers are sometimes allowed.


An Improved Foam Modeling Technique And Its Application To Petroleum Drilling And Production Practice, Yanfang Wang Dec 2020

An Improved Foam Modeling Technique And Its Application To Petroleum Drilling And Production Practice, Yanfang Wang

LSU Doctoral Dissertations

Foam is one of the most common used multiphase fluid in Underbalanced Drilling (UBD) and Managed Pressure Drilling (MPD). Because of its low density, high capacity of lifting and carrying cuttings, low cost and compatibility with formations, foam has become more superior than the conventional drilling mud when depleted reservoir pressure, severe lost circulation, or unstable borehole are encountered. In general, the success of foam applications rely on the understanding of the fundamentals of foam rheology in downhole conditions.

Foam rheology has been studied for decades. Conventional foam rheological models such as Power Law, Bingham Plastic, Herschel-Bulkley to explain foam …


Field Testing The Effects Of Low Reynolds Number On The Power Performance Of The Cal Poly Wind Power Research Center Small Wind Turbine, John B. Cunningham Dec 2020

Field Testing The Effects Of Low Reynolds Number On The Power Performance Of The Cal Poly Wind Power Research Center Small Wind Turbine, John B. Cunningham

Master's Theses

This thesis report investigates the effects of low Reynolds number on the power performance of a 3.74 m diameter horizontal axis wind turbine. The small wind turbine was field tested at the Cal Poly Wind Power Research Center to acquire its coefficient of performance, C­p, vs. tip speed ratio, λ, characteristics. A description of both the wind turbine and test setup are provided. Data filtration and processing techniques were developed to ensure a valid method to analyze and characterize wind power measurements taken in a highly variable environment. The test results demonstrated a significant drop in the …


Numerical Analysis Of A Roadway Piezoelectric Harvesting System, Abdul Rahman Badawi Dec 2020

Numerical Analysis Of A Roadway Piezoelectric Harvesting System, Abdul Rahman Badawi

Mechanical & Aerospace Engineering Theses & Dissertations

Highways, streets, bridges, and sidewalks with heavy traffic dissipate a considerable amount of waste mechanical energy every day. Piezoelectric energy harvesting devices are a very promising technology that can convert the waste mechanical energy to clean and renewable energy to enhance the sustainability of infrastructures. Research efforts in large-scale energy harvesting have led to the advancement of piezoelectric devices to the point that large-scale implementation is starting to become more feasible. The energy harvested by these devices can be used in many ways such as providing heating or cooling, melting ice, monitoring structural conditions in bridges and tunnels, and powering …


Direct Solar Absorption Nanoparticle Doped Membranes For A Hybrid Membrane Distillation And Photovoltaic Cell, Alejandro Espejo Sanchez Dec 2020

Direct Solar Absorption Nanoparticle Doped Membranes For A Hybrid Membrane Distillation And Photovoltaic Cell, Alejandro Espejo Sanchez

Boise State University Theses and Dissertations

The growing demand for clean water supplies is driving the need for an innovative approach of water desalination. Developing a method for treating water with high salinities is possible with membrane distillation (MD). Additionally, MD is very attractive for pairing with solar energy due to the low temperature requirements. The integration of a membrane distillation system with a photovoltaic (PV) system will result in the co-production of electricity and clean water, thereby improving the economics of MD. Such a hybrid system will directly absorb thermal energy in the membrane for desalination while taking advantage of the spectrally selective nature of …


The Energy Efficiency Of Maritime Autonomous Surface Ship (Mass), Dang Cuong Nguyen Nov 2020

The Energy Efficiency Of Maritime Autonomous Surface Ship (Mass), Dang Cuong Nguyen

World Maritime University Dissertations

No abstract provided.


The Application Of Renewable Energy Supply In A Port Container Terminal : Bandar Abbas Port Container Terminal Case Study, Zhila Gordani Nov 2020

The Application Of Renewable Energy Supply In A Port Container Terminal : Bandar Abbas Port Container Terminal Case Study, Zhila Gordani

World Maritime University Dissertations

No abstract provided.


The Energy And Exergy Of Light With Application To Societal Exergy Analysis.Pdf, Matthew K. Heun, Zeke Marshall, Emmanuel Aramendia, Paul E. Brockway Oct 2020

The Energy And Exergy Of Light With Application To Societal Exergy Analysis.Pdf, Matthew K. Heun, Zeke Marshall, Emmanuel Aramendia, Paul E. Brockway

University Faculty Publications and Creative Works

Lighting provides an indispensable energy service, illumination. The field of societal exergy analysis considers light (andmany other energy products) to be enablers of economic growth, and lighting contributes a non-negligible proportion of total useful exergy supplied to modern economies. In societal exergy analysis, the exergetic efficiency of electric lamps is central to determining the exergy contribution of lighting to an economy. Conventionally, societal exergy practitioners estimate the exergetic efficiency of lamps by an energy efficiency, causing confusion and, sometimes, overestimation of exergetic efficiency by a factor as large as 3. In response, we use recent results from the fields of …