80 research outputs found
HVAC Monitoring System
This report outlines the design and implementation stages of the development of a heating, ventilation, and air conditioning (HVAC) airflow, humidity, and temperature monitoring device. The purpose of the device is to collect data to inform manufacturers and users about the current operational status of the HVAC system in place. Information about the airflow, humidity, and temperature is to be collected and wirelessly transmitted to a central database, where the data can be stored for later use and processing. The sensors and transmitter are to be powered using only energy harvested from the system, so that this data can be obtained at no additional cost to the consumer
Dynamic Modeling and Environmental Analysis of Hydrokinetic Energy Extraction
The world is facing an imminent energy supply crisis. Our well-being is linked to the energy supply, and energy is in high demand in both the developed and the developing world. In order to sustain our energy supply, it is necessary to advance renewable technologies. Despite this urgency, however, it is paramount to consider the larger environmental effects associated with using renewable resources.Hydropower, in the past, has been seen as a viable resource to examine, given that its basics of mechanical to electrical energy conversion seem to have little effect on the environment. Discrete analysis of dams and in-stream diversion set-ups has shown otherwise, though. Modifications to river flows and changes in temperature (from increased and decreased flows) cause adverse effects to fish and other marine life because of changes in their adaptive habitat.Recent research has focused on kinetic energy extraction in river flows, which may prove to be more sustainable, as this type of extraction does not involve a large reservoir or large flow modification. The field of hydrokinetic energy extraction is immature; little is known about the devices' performance in the river environment, and their risk of impingement, fouling, and suspension of sediments. Governing principles of hydrokinetic energy extraction are presented, along with a two-dimensional computational fluid dynamics (CFD) model of the system. Power extraction methods are compared, and verification and validation of the CFD model through mesh sensitivity and experimental data are presented. A 0.0506 average mesh skew and 0.2m/s velocity convergence was obtained within the mesh sensitivity analysis. In comparing particle image velocimetry (PIV) data with the CFD model, a 0.0155m offset and 20\% error were present. However, including a volume of fluid (VOF) model within the CFD model produced a 5\% error improvement and gave a 0.0124m offset. These are improvements over the current state of the art, where visual comparisons are common. Three-dimensional CFD models of a submerged water wheel, Savonius turbine, squirrel cage Darrieus turbine, and Gorlov Darrieus turbine are also presented; however, they are non-VOF CFD models.Using the results of the CFD models, preliminary predictions could be made of the environmental impact of hydrokinetic turbines with respect to fish swimming patterns. Additionally, a life cycle assessment (LCA) was conducted for hydrokinetic energy extraction (HEE), which gives insight into the total system environmental impact. HEE has been seen as a potentially ``benign' form of renewable hydropower. This work provides a benchmark for initial measurement of HEE environmental impacts, since negative outcomes have been present with previously-assumed benign renewable hydropower. A Gorlov system was used to represent a HEE system. LCA was utilized to compare the environmental impacts of HEE with small hydropotential (HPP) power, coal, natural gas and nuclear power. Environmental Protection Agency (EPA) criteria air emissions were quantified and compared over the life cycle of the systems. Life cycle air emissions were used in combination with the TRACI impact assessment tool to compare the systems. The Gorlov system was found to have the lowest life cycle impact with a system lifetime comparison, and compared closely with small HPP.Finally, various issues connected to the implementation of hydrokinetic power generation were discussed. Policy development and sediment movement were investigated in more detail. Additionally, two applications of this technology were explored: in-situ river health monitoring and remote energy generation
Energy Harvesting Techniques for Small Scale Environmentally-Powered Electronic Systems
The continuous advances in integrated circuit fabrication technologies, circuit design, and networking techniques enable the integration of an in-creasing number of functionalities in ever smaller devices. This trend de-termines the multiplication of possible application scenarios for tiny em-bedded systems such as wireless sensors, whose utilization has grown more and more pervasive. However, the operating life time of such sys-tems, when placed in locations not allowing a wired connection to a de-pendable power supply infrastructure, is still heavily limited by the finite capacity of currently available accumulators, whose technology has not improved at the same pace of the electronic systems they supply.
Energy harvesting techniques constitute a real solution to power un-tethered computing platforms in this kind of spatially-distributed applica-tions. By converting part of the energy freely available in the surrounding environment to electrical energy, the operating life of the system can be extended considerably, potentially for an unlimited time. In recent years an increasing number of researchers have investigated this possibility.
In this dissertation we discuss our results about the study and design of systems capable of harvesting energy from various regenerative sources. We start with the design of an airflow energy harvester, focusing on the optimization of its power generation and efficiency performances, and obtaining superior results with respect to similar works in literature. Then we deal with the improvement of this architecture to implement a fully autonomous vibrational harvester, featuring uncommon in-the-field configuration capabilities. Afterwards we investigate the applicability of self-powered wireless sensor nodes to heavy duty and agricultural machinery, finding attractive vibration sources capable of providing enough power to sustain remarkable data transmission rates. To address remote monitoring applications with stringent needs in terms of power supply availability, we present a truly flexible multi-source energy harvester, along with a simulation framework expressly developed to anticipate the harvester performance when placed in a specific operating environment. Furthermore, the design strategies allowing energy harvesters to fully exploit the locally generated power can be profitably applied in the field of distributed electricity generation from renewable energy sources, to enhance the self-consumption capabilities of microgeneration systems. Based on this motivation, we finally propose a grid-assisted photovoltaic power supply to improve the self-sustainability of ground-source heat pumps, and analyze original data on the consumption profiles of these systems to assess the effectiveness of the design.
Energy harvesting techniques have the potential to enable many cut-ting-edge applications, especially in remote sensing and pervasive computing areas, which can bring innovations in several fields of human activity. In this thesis we contribute tackling some of the numerous open research challenges still hampering the widespread adoption of this technology
Numerical Simulation of Wind Turbines
The book contains the research contributions belonging to the Special Issue "Numerical Simulation of Wind Turbines", published in 2020-2021. They consist of 15 original research papers and 1 editorial. Different topics are discussed, from innovative design solutions for large and small wind turbine to control, from advanced simulation techniques to noise prediction. The variety of methods used in the research contributions testifies the need for a holistic approach to the design and simulation of modern wind turbines and will be able to stimulate the interest of the wind energy community
Advanced Techniques for Design and Manufacturing in Marine Engineering
Modern engineering design processes are driven by the extensive use of numerical simulations; naval architecture and ocean engineering are no exception. Computational power has been improved over the last few decades; therefore, the integration of different tools such as CAD, FEM, CFD, and CAM has enabled complex modeling and manufacturing problems to be solved in a more feasible way. Classical naval design methodology can take advantage of this integration, giving rise to more robust designs in terms of shape, structural and hydrodynamic performances, and the manufacturing process.This Special Issue invites researchers and engineers from both academia and the industry to publish the latest progress in design and manufacturing techniques in marine engineering and to debate the current issues and future perspectives in this research area. Suitable topics for this issue include, but are not limited to, the following:CAD-based approaches for designing the hull and appendages of sailing and engine-powered boats and comparisons with traditional techniques;Finite element method applications to predict the structural performance of the whole boat or of a portion of it, with particular attention to the modeling of the material used;Embedded measurement systems for structural health monitoring;Determination of hydrodynamic efficiency using experimental, numerical, or semi-empiric methods for displacement and planning hulls;Topology optimization techniques to overcome traditional scantling criteria based on international standards;Applications of additive manufacturing to derive innovative shapes for internal reinforcements or sandwich hull structures
The Development of an Adaptive Control System for a Phase-Locked Excitation (PhLEX) Method for Advanced Wind Turbine Blade Fatigue Testing
The National Renewable Energy Laboratory\u27s (NREL) National Wind Technology Center (NWTC) provides the means necessary for advanced wind turbine blade testing. To improve on the current testing methods, a new testing method is being developed using the existing dual-axis fatigue testing capabilities in conjunction with another actuator to provide a phase-locked excitation method with adaptive algorithms and advanced control system strategies. This testing method will provide a more representative loading of the blade for fatigue testing as compared to loading seen in the field. The control system will integrate the MTS software and controller with a supervisory controller, programmed in Simulink, which utilizes PID control and peak detection. A Simulink model of a wind turbine blade was incorporated for initial control system design. The use of Hardware-ln-the-Loop (HIL) and Software-ln-the-Loop (SIL) testing methods will be employed for fault testing before the full system test for verification and validation of the control system requirements. This paper will focus on the control system design and simulation results, as well as PID optimization and a Design Failure Modes Effects Analysis that was done to ensure safety of the test
Engineering Dynamics and Life Sciences
From Preface:
This is the fourteenth time when the conference “Dynamical Systems: Theory
and Applications” gathers a numerous group of outstanding scientists and engineers, who
deal with widely understood problems of theoretical and applied dynamics.
Organization of the conference would not have been possible without a great effort of
the staff of the Department of Automation, Biomechanics and Mechatronics. The patronage
over the conference has been taken by the Committee of Mechanics of the Polish Academy
of Sciences and Ministry of Science and Higher Education of Poland.
It is a great pleasure that our invitation has been accepted by recording in the history
of our conference number of people, including good colleagues and friends as well as a large
group of researchers and scientists, who decided to participate in the conference for the
first time. With proud and satisfaction we welcomed over 180 persons from 31 countries all
over the world. They decided to share the results of their research and many years
experiences in a discipline of dynamical systems by submitting many very interesting
papers.
This year, the DSTA Conference Proceedings were split into three volumes entitled
“Dynamical Systems” with respective subtitles: Vibration, Control and Stability of Dynamical
Systems; Mathematical and Numerical Aspects of Dynamical System Analysis and
Engineering Dynamics and Life Sciences. Additionally, there will be also published two
volumes of Springer Proceedings in Mathematics and Statistics entitled “Dynamical Systems
in Theoretical Perspective” and “Dynamical Systems in Applications”
Aeronautical Engineering: A continuing bibliography, supplement 120
This bibliography contains abstracts for 297 reports, articles, and other documents introduced into the NASA scientific and technical information system in February 1980
A Supportive Framework for the Development of a Digital Twin for Wind Turbines Using Open-Source Software Tiril Malmedal Mechanics and Process Technology
The world is facing a global climate crisis. Renewable energy is one of the big solutions, nevertheless, there are technological challenges. Wind power is an important part of the renewable energy system. With the digitalization of industry, smart monitoring and operation is an important step towards efficient use of resources. Thus, Digital Twins (DT) should be applied to enhance power output.
Digital Twins for energy systems combine many fields of study, such as smart monitoring, big data technology, and advanced physical modeling. Frameworks for the structure of Digital Twins are many, but there are few standardized methods based on the experience of such developed Digital Twins.
An integrative review on the topic of Digital Twins with the goal of creating a conceptual development framework for DTs with open-source software is performed. However, the framework is yet to be tested experimentally but is nevertheless an important contribution toward the understanding of DT technology development.
The result of the review is a seven-step framework identifying potential components and methods needed to create a fully developed DT for the aerodynamics of a wind turbine. Suggested steps are Assessment, Create, Communicate, Aggregate, Analyze, Insight, and Act. The goal is that the framework can stimulate more research on digital twins for small-scale wind power. Thus, making small-scale wind power more accessible and affordable
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