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Energy efficiency

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Full-Text Articles in Mechanical Engineering

Towards Real-Time Energy Efficiency Analysis Of A Hydraulic System, Montasir Mamun Mithu Aug 2021

Towards Real-Time Energy Efficiency Analysis Of A Hydraulic System, Montasir Mamun Mithu

Masters Theses

The study aims at developing a real-time data analysis system for the energy efficiency study of hydraulic systems. It also aims at implementing automation for hydraulic systems so that energy efficiency can be improved using the real-time approach. This research uses a system-level experimental methodology. A linear push system hydraulic prototype is developed for the study. The prototype contains hydraulic actuator, shock absorber, electronic flow control valve, and electronic sensor. This prototype is used to experiment with different operating conditions to characterize hydraulic system behavior. A real-time data analysis system is developed using LabVIEW and an Open Platform Communication (OPC) …


Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth Aug 2021

Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth

Mechanical and Aerospace Engineering Dissertations

Evaporative cooling is an alternative data center cooling solution that presents significant energy cost savings in acquisition and operation when compared to conventional air conditioning and mechanical refrigeration systems. This research focuses on developing a deeper understanding in implementing, operating and maintaining evaporative cooling systems integrated with air-side economization to realize the energy savings potential in data center cooling. The goal of the research is to develop a comprehensive guide to assess and contrast different approaches of evaporative cooling being used in data center cooling and provide guidance in improving water and energy efficiency. An air handling unit (AHU) serves …


The Optimization Of Efficiency And Infrastructure For Modern Potable Water Treatment Plants, Brent A. Dekock Dec 2020

The Optimization Of Efficiency And Infrastructure For Modern Potable Water Treatment Plants, Brent A. Dekock

Theses and Dissertations

The USDOE Industrial Assessment Centers (IACs) is a program that is designed to help small and medium-sized manufacturing facilities reduce their overall costs and improve energy efficiency. This includes improving potable water treatment plants which supply water throughout the country. This thesis covers the process of how IAC branches and water treatment facilities generally operate, as well as several assessment recommendations that have been developed by a branch of the IAC for several water treatment plants based in the Rio Grande Valley of Texas. The steps of the assessment and water treatment process are described, and several cost saving measures …


Sundown: Model-Driven Per-Panel Solar Anomaly Detection For Residential Arrays, Menghong Feng Jul 2020

Sundown: Model-Driven Per-Panel Solar Anomaly Detection For Residential Arrays, Menghong Feng

Masters Theses

There has been significant growth in both utility-scale and residential-scale solar installa- tions in recent years, driven by rapid technology improvements and falling prices. Unlike utility-scale solar farms that are professionally managed and maintained, smaller residential- scale installations often lack sensing and instrumentation for performance monitoring and fault detection. As a result, faults may go undetected for long periods of time, resulting in generation and revenue losses for the homeowner. In this thesis, we present SunDown, a sensorless approach designed to detect per-panel faults in residential solar arrays. SunDown does not require any new sensors for its fault detection and …


Development And Testing Of A Control Strategy For Dynamic Cooling At Rack Level In Data Centers, Amrutha Valli Rachakonda Dec 2019

Development And Testing Of A Control Strategy For Dynamic Cooling At Rack Level In Data Centers, Amrutha Valli Rachakonda

Mechanical and Aerospace Engineering Theses

Cooling is a critical part of data center’s infrastructure, and with ongoing demands in data processing and storage, thermal management issues are of great concern. Some imperative methods of removing heat are either using air or liquid (preferably water or refrigerant). When high power density modules are involved, liquid cooling addresses some of the problems faced by air cooling as liquid coolants have higher thermal capacitance. Also, in the case of multi-chip modules, a non-uniform heating due to multi-core generates hot-spots and increases temperature gradients across the module. A dynamic cold plate along with a self-regulated flow control device was …


Manufacturing Energy Consumption And Assessment For Us Small And Medium Sized Manufacturers, Yadan Zeng Dec 2018

Manufacturing Energy Consumption And Assessment For Us Small And Medium Sized Manufacturers, Yadan Zeng

Theses and Dissertations

U.S. Manufacturing sector consumes remarkable amount of energy while the energy efficiency is quite low. Energy consumption of CNC machines is significant and various empirical models have been developed to model the Specific Energy Consumption (SEC) of CNC machines. However, most of the models are developed for specific machines, hence have limited applications in manufacturing industry. In this research, a general empirical SEC model for milling machine at certain power level is developed based on actual cutting experimental data. In this model, stand-by power and spindle power are used in the SEC model for the first time. The Material Removal …


Demand Side Management For Building Energy Efficiency Through Hybrid Daylighting System And Battery Energy Storage System, Tonghui Li May 2018

Demand Side Management For Building Energy Efficiency Through Hybrid Daylighting System And Battery Energy Storage System, Tonghui Li

Theses and Dissertations

This dissertation aims to investigate demand side management (DSM) to improve building energy efficiency and reduce on-peak electricity demand. Daylighting device and battery energy storage system (BESS) for peak shaving are proposed and studied. To reduce the cost and improve the efficiency of building lighting, an innovative parabolic trough solar lighting and thermal (PTL/T) system is designed and analyzed. In the proposed system, a parabolic trough collector (PTC) controlled by two-axis solar tracking system is used as solar collector. The collected sunlight is split by a cold mirror into visible light and infrared light. The visible light is reflected by …


Experimental And Computational Study Of Multi-Level Cooling Systems At Elevated Coolant Temperatures In Data Centers, Manasa Sahini Aug 2017

Experimental And Computational Study Of Multi-Level Cooling Systems At Elevated Coolant Temperatures In Data Centers, Manasa Sahini

Mechanical and Aerospace Engineering Dissertations

Data centers house a variety of compute, storage, network IT hardware where equipment reliability is of utmost importance. Heat generated by the IT equipment can substantially reduce its service life if T_(J,Max), maximum temperature that the microelectronic device tolerates to guarantee reliable operation, is exceeded. Hence, data center rooms are bound to maintain continuous conditioning of the cooling medium. This approach often results in over-provisioned cooling systems. In 2014, U.S. Data center electricity consumption is about 1.8% of the total electrical energy in the country. Hence, data center power and cooling have become significant issues facing the IT industry. The …


Evaluating The Performance Of Passive Chilled Beams With Respect To Energy Efficiency And Thermal Comfort, Janghyun Kim Dec 2016

Evaluating The Performance Of Passive Chilled Beams With Respect To Energy Efficiency And Thermal Comfort, Janghyun Kim

Open Access Dissertations

Existing modeling approaches for passive chilled beams determined from tests on individual chilled beams in a laboratory are not adequate for assessing overall energy usage and occupant comfort within building simulation programs. In addition, design guidelines for passive chilled beam systems are needed for identifying appropriate applications and optimal configurations. This thesis includes (i) extensive experimental studies for characterizing the performance of passive chilled beams, in both laboratory settings and in field studies, (ii) development of passive chilled beam performance prediction models, (iii) integration of these models into building simulation models/tools and (iv) use of building simulation for overall assessment …


How Can Occupancy Modeling And Occupancy Sensors Reduce Energy Usage In Academic Buildings: An Application Approach To University Of San Francisco, Paloma R. Duong May 2016

How Can Occupancy Modeling And Occupancy Sensors Reduce Energy Usage In Academic Buildings: An Application Approach To University Of San Francisco, Paloma R. Duong

Master's Projects and Capstones

Buildings are amongst the highest energy consumers relative to industry and transportation. They account for 40% of the world’s energy consumption, due to the need for lighting, equipment, heating, cooling and ventilation. Academic buildings are multi-purpose buildings that create a challenge on energy reduction. Most are old and have fixed occupancy schedules, resulting in high energy consumption because these buildings experience significant occupancy variation throughout the day. Five academic buildings were analyzed; their building information, energy consumption data and methods to project energy savings have been analyzed. The case studies presented different strategies on predicting energy savings, but these have …


Operational Planning In Combined Heat And Power Systems, Hariharan Gopalakrishnan Nov 2014

Operational Planning In Combined Heat And Power Systems, Hariharan Gopalakrishnan

Doctoral Dissertations

This dissertation presents methodologies for operational planning in Combined Heat and Power (CHP) systems. The subject of experimentation is the University of Massachusetts CHP system, which is a 22 MWe/640 MBh system for a district energy application. Systems like this have complex energy flow networks due to multiple interconnected thermodynamic components like gas and steam turbines, boilers and heat recovery steam generators and also interconnection with centralized electric grids. In district energy applications, heat and power requirements vary over 24 hour periods (planning horizon) due to changing weather conditions, time-of-day factors and consumer requirements. System thermal performance is highly dependent …


Improving Indoor Air Quality Through Botanical Air Filtration In Energy Efficient Residences, Daniel William Newkirk Apr 2014

Improving Indoor Air Quality Through Botanical Air Filtration In Energy Efficient Residences, Daniel William Newkirk

Open Access Theses

According to the U.S. EPA, the average American spends 90% of their time indoors where pollutants are two to five times more prevalent than outside. The consequences of these pollutants are estimated to cost the U.S. 125 billion dollars in lost health and productivity. Background literature suggests botanical air filtration may be able to solve this problem by leveraging the natural ability of plants to purify indoor air. By improving indoor air quality, energy consumption can also be reduced by bringing in less outside air to dilute contaminants within the space. A botanical air filter, called the Biowall, was designed …


A Metaevaluation Of Energy Efficiency Evaluations, Brandy Brown Apr 2014

A Metaevaluation Of Energy Efficiency Evaluations, Brandy Brown

Dissertations

This study systematically reviews the methodological characteristics of energy efficiency evaluations and uses metaevaluation to assess its quality. Metaevaluation is used to systematically assess the quality of evaluation products, confirm that evaluations deliver sound findings and conclusions, are useful to the client, are credible, are ethically conducted, and are done as cost-effective as possible. The results of this study show that the ability to accurately assess evaluation for methodological quality using evaluations reports as a primary data source depends on the presence of detailed descriptions of evaluation methods. Furthermore, the study suggests that methodological variations of energy efficiency evaluations coalesce …


Plasmonics Resonance Enhanced Active Photothermal Effects In Aluminum Nanoenergetics For Propulsion Applications, Jacques Abboud Aug 2013

Plasmonics Resonance Enhanced Active Photothermal Effects In Aluminum Nanoenergetics For Propulsion Applications, Jacques Abboud

Doctoral Dissertations

In this dissertation, aluminum nanoparticles (Al NPs) are shown capable to on-demand enhance and control the local photothermal energy deposition, both spatially and temporally, via active photothermal effects initiated by the localized surface plasmon resonance (LSPR) phenomenon, and amplified by the Al exothermal oxidation reactions. Experiments in dry and wet environments along with computational modeling of the photothermal process are very desirable for gaining fundamental understanding, ignition optimization and parameter exploration.

Combined phenomena of motion and ignition of Al NPs are explored first in this study. Both resulting from exposing a pile of the nanoenergetics in hand to a single …


Design Of An Energy Efficient Virtual End Node Client Using Openadr2.0a And Smap, Kevin Navero Jun 2013

Design Of An Energy Efficient Virtual End Node Client Using Openadr2.0a And Smap, Kevin Navero

BioResource and Agricultural Engineering

Demand Response (DR) describes the set of actions taken to impose a reduction in electrical loads to stabilize the power grid and decrease costs. It is used when power grid emergencies or extremely high demand and congestion, threaten the electricity supply-demand balance. Automated Demand Response (ADR) describes a web-based control system that triggers DR events automatically by signaling other pre-programmed control systems. This project intends to use the OpenADR2.0 specifications provided by the OpenADR Alliance to construct an open source Virtual End Node (VEN) client to retrieve DR signals. The Simple Measurement and Actuation Profile (sMAP) software is also used …


Investigation Of Peak Load Reduction Strategies In Residential Buildings In Cooling Dominated Climates, Fady Atallah May 2013

Investigation Of Peak Load Reduction Strategies In Residential Buildings In Cooling Dominated Climates, Fady Atallah

UNLV Theses, Dissertations, Professional Papers, and Capstones

This investigation of peak load reduction strategies in residential buildings contributes to the global international efforts in reducing energy consumption and is related directly to energy efficiency in residential and commercial buildings. Work reported here involves computer aided building energy simulation of energy efficient and non-energy efficient residential homes coupled with empirical energy consumption data gathered from monitoring an array of energy efficient residential homes. The latter have been implemented for peak load reduction strategies. In addition non-energy efficient residential homes have been monitored to compare performance to the energy efficient homes. This study demonstrates the crucial importance of energy …


Reconfigurable Sampling For Enhanced Energy Efficiency In Power-Constrained Wireless Systems, Timothy Kurp Jun 2011

Reconfigurable Sampling For Enhanced Energy Efficiency In Power-Constrained Wireless Systems, Timothy Kurp

Master's Theses

Advancement in microelectronics and wireless communications has nurtured the development of low power and low cost wireless systems such as sensor networks. Each node is typically driven by a battery, which has a limited energy capacity that directly constrains node, and network lifetime. This presents a bottleneck for the widespread exploitation of wireless sensing technology. Therefore, improving the energy efficiency of wireless sensing devices is of critical importance and has attracted the attention of the research community.

In this work, a data-driven method has been proposed and systematically investigated. Specifically, this technique reconfigures, in real time, the rate of data …


The Optimized Electrostatic Motor, Christopher Lee Rambin Jul 1998

The Optimized Electrostatic Motor, Christopher Lee Rambin

Doctoral Dissertations

The most common means of electrically activated actuation is the electromagnetic motor. All electromagnetic motors have a low output to weight ratio and low energy efficiency. The motor's weight is due to the coils and magnets used to generate propulsion. The energy loss is mainly the result of Joule heating that is inherent with any current driven device. An electrostatic motor offers the potential of significantly less weight and higher energy efficiency. This lower weight characteristic is due to the epoxide material used to construct the major components of its propulsion unit. Greater efficiency results from the reduced Joule heating …