Mechanical Engineering Commons^™

Electromagnetic Modeling Of A Wind Tunnel Magnetic Suspension And Balance System, Desiree Driver

Mechanical & Aerospace Engineering Theses & Dissertations

Wind tunnels are used to study forces and moments acting on an aerodynamic body. While most results involve some interference from the mechanical supports used to hold the model, a Magnetic Suspension and Balance System (MSBS) is void of these interferences and presents an ideal test scenario. To further investigate the feasibility of dynamic stability testing at supersonic speeds using a MSBS, a preliminary design idea is currently being developed using an existing MSBS in a subsonic wind tunnel. This review focuses on the development of a mathematical model to more accurately portray the capabilities of the 6 inch Massachusetts …

Detailed Modeling Of The Flash Hydrolysis Of Algae For Biofuel-Production In Comsol Multiphysics, Noah Joseph Legrand

Mechanical & Aerospace Engineering Theses & Dissertations

Algae-derived biofuels are being commercialized as an important renewable energy source. Like any new technology, conversion improvements are desired, including reductions in process complexity and better utilization of the entire microalgae feedstock. The Old Dominion Biomass Laboratory has focused on flash hydrolysis for algae biofuel production. That process involves rapidly heating algae and water mixed as a slurry to a subcritical state. Results from small-scale bench tests are promising, but process scale up is a challenge. Currently there exists a pilot laboratory scale system utilizing induction heating in order to reach controlled reaction temperatures with a reaction duration of 10 …

Isogeometric Analysis For Electromagnetism, Tahsin Khajah

Mechanical & Aerospace Engineering Theses & Dissertations

The combination of numerical analysis with the scanning technology has been seeing increased use in many research areas. There is an emerging need for high-fidelity geometric modeling and meshing for practical applications. The Isogeometric Analysis (IGA) is a comprehensive computational framework, which integrates geometric modeling and meshing with analysis. Different from other existing numerical methods, the IGA can generate analysis ready models without loss of geometrical accuracy. In IGA, the continuity and the quality of a solution can be conveniently controlled and refined. These features enable IGA to integrate modeling, analysis, and design in a unified framework, the root idea …

Modeling, Identification, Validation And Control Of A Hybrid Maglev Ball System, Ahmed Elhussein E. Mekky

Mechanical & Aerospace Engineering Theses & Dissertations

In this thesis, the electrodynamics of a single axis hybrid electromagnetic suspension Maglev system was modeled and validated by applying it to a single axis hybrid maglev ball experiment. By exploring its linearized model, it was shown that the single axis hybrid Maglev ball has inherently unstable dynamics. Three control scenarios were explored based on the linearized model; (1) Proportional, Deferential (PD) control, (2) Proportional, Deferential, Integral (PID) and (3) PID controller with pre-filtering. This thesis has shown that a PID controller with a pre-filtering technique can stabilize such a system and provide a well-controlled response.

A parametric system identification …

Stability Analysis, Modeling, Simulation And Experimental Testing Of An Ems Maglev System With Structural Flexibility, Aravind M. Hanasoge

Mechanical & Aerospace Engineering Theses & Dissertations

Vehicle-guideway interaction studies of Magnetically Levitated (Maglev) vehicles indicate that structural flexibility can adversely affect the overall stability and performance of such systems. This is one of the reasons why guideways are generally made very rigid. This in turn leads to increased cost of the overall system since guideway construction forms a significant portion of the overall cost. In this dissertation, the influence of structural flexibility on the stability of Electromagnetic Suspension (EMS) Maglev systems is studied. It is shown how inherently unstable and flexible structure EMS Maglev systems can achieve guaranteed stability by using collocated actuators and sensors, along …

Analysis Of Possible Use Of Identification Technologies In Disassembly, Vukica Jovanović, Sreten Filipović, Gordana Ostojić, Stevan Stankovski, Milovan Lazarević

Engineering Technology Faculty Publications

The barcodes and Radio Frequency Identification tags that are being used during manufacturing, assembly, warehousing, and distribution could also be reused at the end of the product lifecycle for an identification of the correct disassembly process that would result in recycling of its components. The barcodes or RFID tags can be helpful in identifying objects in terms of sustainable development, regarding disassembly, recycling and reuse. In this paper, the analysis of the current applications of RFID Technology in the final phase of the product lifecycle will be presented. The simulation of the disassembly process supported by both barcode and RFID-enabled …

Using Rfid Technology In Collaborative Design Of The Assembly Systems, Stevan Stankovski, Gordana Ostojić, Vukica Jovanović, Branislav Stevanov

Engineering Technology Faculty Publications

Modern production conditions require the application of the concept of distributing production. This approach means coordinative production in a number of small and middle size companies. Multiplex products, consisting of a number of parts, components, and modules are assembled in one function unit in one company, but they may not be manufactured in one place. Huge factory and production complex, which existed in our country, comprised all phases of product lifecycle, from the development of a concept solution to the assembly. Technology of product manufacturing, resource logistics, quality control, product testing and verification of product function characteristics all represented activities …

Rfid Technology Use In Assembly And Disassembly Processes, Gordana Ostojić, Milovan Lazarević, Vukica Jovanović, Stevan Stankovski, Ilija Ćosić

Engineering Technology Faculty Publications

Modern production conditions demand the application of the concept of distributed production. Today companies are specialized for partial technology processes. Hundreds, sometimes even thousands, of collaborative processes depend on workers’ interaction and communication in product assembly and disassembly phases. RFID technologies can be really helpful in identifying objects in terms of sustainable development, regarding disassembly, recycling and reuse. In this paper we presented VCDE system architecture and the realization method of RFID technology as well as the data acquisition using RFID technology during the product lifecycle from the design process, production, assembly, usage, and an special example is given regard- …

Robustness And Control Of A Magnetically Levitated Transportation System, Grzegorz Oleszczuk

Mechanical & Aerospace Engineering Theses & Dissertations

Electromagnetic suspension of Magnetic Levitation Vehicles (Maglev) has been studied for many years as an alternative to wheel-on rail transportation systems. In this work, design and implementation of control systems for a Maglev laboratory experiment and a Maglev vehicle under development at Old Dominion University are described. Both plants are modeled and simulated with consideration of issues associated with system non-linearity, structural flexibility and electromagnetic force modeling. Discussion concerning different control strategies, namely centralized and decentralized approaches are compared and contrasted in this work. Different types of electromagnetic non-linearities are considered and described to establish a convenient method for modeling …

A Magnetic Suspension System With A Large Angular Range, Colin P. Britcher, Mehran Ghofrani

Mechanical & Aerospace Engineering Faculty Publications

In order to explore and develop technology required for the magnetic suspension of objects over large ranges of orientation, a small-scale laboratory system, the large-angle magnetic suspension test fixture (LAMSTF) has been constructed at NASA Langley Research Center. This apparatus falls into the category of large-gap, actively stabilized magnetic levitation systems. The hardware comprises five conventional electromagnets in a circular arrangement, each driven from a separate bipolar power amplifier. Electromagnet currents are commanded by a digital control system, implemented on a microcomputer, which in turn derives the position and attitude of the suspended element from an infrared optical system. The …