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Full-Text Articles in Mechanical Engineering

Me-Em 2019-20 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University Sep 2020

Me-Em 2019-20 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical Engineering-Engineering Mechanics Annual Reports

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Power Take-Off And Energy Storage System Static Modeling And Sizing For Direct Drive Wave Energy Converter To Support Ocean Sensing Applications, Xiang Zhou, Ossama Abdelkhalik, Wayne Weaver Jul 2020

Power Take-Off And Energy Storage System Static Modeling And Sizing For Direct Drive Wave Energy Converter To Support Ocean Sensing Applications, Xiang Zhou, Ossama Abdelkhalik, Wayne Weaver

Michigan Tech Publications

This paper addresses the sizing and design problem of a permanent magnet electrical machine power take-off system for a two-body wave energy converter, which is designed to support ocean sensing applications with sustained power. The design is based upon ground truth ocean data bi-spectrums (swell and wind waves) from Martha’s Vineyard Coastal Observatory in the year 2015. According to the ground truth ocean data, the paper presents the optimal harvesting power time series of the whole year. The electrical machine and energy storage static modeling are introduced in the paper. The paper uses the ground truth ocean data in ...


Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce Jun 2020

Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications

To assist firefighters and other first responders to use their existing equipment for respiration during the COVID-19 pandemic without using single-use, low-supply, masks, this study outlines an open source kit to convert a 3M-manufactured Scott Safety self-contained breathing apparatus (SCBA) into a powered air-purifying particulate respirator (PAPR). The open source PAPR can be fabricated with a low-cost 3-D printer and widely available components for less than $150, replacing commercial conversion kits saving 85% or full-fledged proprietary PAPRs saving over 90%. The parametric designs allow for adaptation to other core components and can be custom fit specifically to fire-fighter equipment, including ...


Me-Em Enewsbrief, June 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University Jun 2020

Me-Em Enewsbrief, June 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical Engineering-Engineering Mechanics eNewsBrief

No abstract provided.


Sparse And Random Sampling Techniques For High-Resolution, Full-Field, Bss-Based Structural Dynamics Identification From Video, Bridget Martinez, Andre Green, Moises Felipe Silva, David Mascareñas, Yongchao Yang Jun 2020

Sparse And Random Sampling Techniques For High-Resolution, Full-Field, Bss-Based Structural Dynamics Identification From Video, Bridget Martinez, Andre Green, Moises Felipe Silva, David Mascareñas, Yongchao Yang

Michigan Tech Publications

Video-based techniques for identification of structural dynamics have the advantage that they are very inexpensive to deploy compared to conventional accelerometer or strain gauge techniques. When structural dynamics from video is accomplished using full-field, high-resolution analysis techniques utilizing algorithms on the pixel time series such as principal components analysis and solutions to blind source separation the added benefit of high-resolution, full-field modal identification is achieved. An important property of video of vibrating structures is that it is particularly sparse. Typically video of vibrating structures has a dimensionality consisting of many thousands or even millions of pixels and hundreds to thousands ...


Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met ...


Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce May 2020

Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Access to nasopharyngeal swabs for sampling remain a bottleneck in some regions for COVID19 testing. This study develops a distributed manufacturing solution using only an open source manufacturing tool chain consisting of two types of open source 3-D printing and batch UV curing, and provides a parametric fully free design of a nasopharyngeal swab. The swab was designed using parametric OpenSCAD in two components (a head with engineered break point and various handles), which has several advantages: i) minimizing print time on relatively slow SLA printers, ii) enabling the use of smaller print volume open source SLA printers, iii) reducing ...


Chlorine Removal From U.S. Solid Waste Blends Through Torrefaction, Zhuo Xu, Josh W. Albrecht, Shreyas Kolapkar, Stas Zinchik, Ezra Bar Ziv May 2020

Chlorine Removal From U.S. Solid Waste Blends Through Torrefaction, Zhuo Xu, Josh W. Albrecht, Shreyas Kolapkar, Stas Zinchik, Ezra Bar Ziv

Michigan Tech Publications

The amount of solid waste generated annually is increasing around the world. Although the waste has a high calorific value, one major obstacle that may prevent it from becoming a feedstock for power applications is the existence of polyvinyl chloride (PVC), which causes corrosion and emission issues after combustion due to its high chlorine content. Torrefaction is known to release hydrochloric acid; thus, it has been applied in this study for the reduction of chlorine from potential waste feedstocks. Fiber-plastic (60-40%) waste blends, with different chlorine content levels, as well as PVC were used in the current study. Torrefaction was ...


Energy Storage Power And Energy Sizing And Specification Using Hsspfc, Mehrzad M. Bijaieh, Wayne Weaver, Rush D. Robinett Iii Apr 2020

Energy Storage Power And Energy Sizing And Specification Using Hsspfc, Mehrzad M. Bijaieh, Wayne Weaver, Rush D. Robinett Iii

Michigan Tech Publications

The intermittent nature of renewable sources requires the integration of Energy Storage Systems (ESSs) with appropriate power and energy densities. One of the applications of Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) is to size ESSs for power and energy densities by employing them as sole actuators of Microgrid (MG) systems. This Article provides a comprehensive yet simplified example of utilization of HSSPFC to size ESSs of inverter-based three-phase MG systems under hierarchical control. Here, the distributed Hamiltonian controller is expanded for control of parallel ESSs and power sharing metrics are defined to distribute power between hybrid storage systems ...


Electric Vehicle-Grid Integration With Voltage Regulation In Radial Distribution Networks, Chong Cao, Zhouquan Wu, Bo Chen Apr 2020

Electric Vehicle-Grid Integration With Voltage Regulation In Radial Distribution Networks, Chong Cao, Zhouquan Wu, Bo Chen

Michigan Tech Publications

In this paper, a vehicle-grid integration (VGI) control strategy for radial power distribution networks is presented. The control schemes are designed at both microgrid level and distribution level. At the VGI microgrid level, the available power capacity for electric vehicle (EV) charging is optimally allocated for charging electric vehicles to meet charging requirements. At the distribution grid level, a distributed voltage compensation algorithm is designed to recover voltage violation when it happens at a distribution node. The voltage compensation is achieved through a negotiation between the grid-level agent and VGI microgrid agents using the alternating direction method of multipliers. In ...


Me-Em Enewsbrief, March 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University Mar 2020

Me-Em Enewsbrief, March 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical Engineering-Engineering Mechanics eNewsBrief

No abstract provided.


Fracture Toughness Analysis Of Epoxy-Recycled Rubber-Based Composite Reinforced With Graphene Nanoplatelets For Structural Applications In Automotive And Aeronautics, Alaeddin Burak Irez, Emin Bayraktar, Ibrahim Miskioglu Feb 2020

Fracture Toughness Analysis Of Epoxy-Recycled Rubber-Based Composite Reinforced With Graphene Nanoplatelets For Structural Applications In Automotive And Aeronautics, Alaeddin Burak Irez, Emin Bayraktar, Ibrahim Miskioglu

Michigan Tech Publications

This study proposes a new design of lightweight and cost-efficient composite materials for the aeronautic industry utilizing recycled fresh scrap rubber, epoxy resin, and graphene nanoplatelets (GnPs). After manufacturing the composites, their bending strength and fracture characteristics were investigated by three-point bending (3PB) tests. Halpin-Tsai homogenization adapted to composites containing GnPs was used to estimate the moduli of the composites, and satisfactory agreement with the 3PB test results was observed. In addition, 3PB tests were simulated by finite element method incorporating the Halpin-Tsai homogenization, and the resulting stress-strain curves were compared with the experimental results. Mechanical test results showed that ...


Publisher Correction: Evaporation Of A Sessile Droplet On A Slope., Mitch Timm, Esmaeil Dehdashti, Amir Jarrahi Darban, Hassan Masoud Feb 2020

Publisher Correction: Evaporation Of A Sessile Droplet On A Slope., Mitch Timm, Esmaeil Dehdashti, Amir Jarrahi Darban, Hassan Masoud

Michigan Tech Publications

An amendment to this paper has been published and can be accessed via a link at the top of the paper.


Characterizing Meteorological Forecast Impact On Microgrid Optimization Performance And Design, Robert Jane, Gordon G. Parker, Gail Vaucher, Morris Berman Jan 2020

Characterizing Meteorological Forecast Impact On Microgrid Optimization Performance And Design, Robert Jane, Gordon G. Parker, Gail Vaucher, Morris Berman

Michigan Tech Publications

A microgrid consists of electrical generation sources, energy storage assets, loads, and the ability to function independently, or connect and share power with other electrical grids. Thefocus of this work is on the behavior of a microgrid, with both diesel generator and photovoltaic resources, whose heating or cooling loads are influenced by local meteorological conditions. Themicrogrid's fuel consumption and energy storage requirement were then examined as a function of the atmospheric conditions used by its energy management strategy (EMS). A fuel-optimal EMS, able to exploit meteorological forecasts, was developed and evaluated using a hybrid microgrid simulation. Weather forecast update ...


Optimal Mission Planning Of Autonomous Mobile Agents For Applications In Microgrids, Sensor Networks, And Military Reconnaissance, Casey D. Majhor Jan 2020

Optimal Mission Planning Of Autonomous Mobile Agents For Applications In Microgrids, Sensor Networks, And Military Reconnaissance, Casey D. Majhor

Dissertations, Master's Theses and Master's Reports

As technology advances, the use of collaborative autonomous mobile systems for various applications will become evermore prevalent. One interesting application of these multi-agent systems is for autonomous mobile microgrids. These systems will play an increasingly important role in applications such as military special operations for mobile ad-hoc power infrastructures and for intelligence, surveillance, and reconnaissance missions. In performing these operations with these autonomous energy assets, there is a crucial need to optimize their functionality according to their specific application and mission. Challenges arise in determining mission characteristics such as how each resource should operate, when, where, and for how long ...


Dynamic Testing: An Experimental Approach To Defect Identification In Additive Manufactured Parts, Aimee Allen Jan 2020

Dynamic Testing: An Experimental Approach To Defect Identification In Additive Manufactured Parts, Aimee Allen

Dissertations, Master's Theses and Master's Reports

Today’s additive manufacturing (AM) industry produces specialized parts at low volume or with complex geometries. Traditional testing methods are effective, but costly and time consuming to perform. The AM industry lacks an optimized testing method for identifying internal defects that occur in parts. The evaluation of multiple parts printed on the same build plate for internal defects using various nondestructive (dynamic) testing techniques is presented. From these experiments, perspective was gained on when and how dynamic testing can be used to find defects. Insight gained from these experiments can help the industry in future testing for internal defects.


Multiscale Modeling Of Carbon Fibers/Graphene Nanoplatelets/Epoxy Hybrid Composites For Aerospace Applications, Hashim Al Mahmud Jan 2020

Multiscale Modeling Of Carbon Fibers/Graphene Nanoplatelets/Epoxy Hybrid Composites For Aerospace Applications, Hashim Al Mahmud

Dissertations, Master's Theses and Master's Reports

Significant research effort has been dedicated for decades to improve the mechanical properties of aerospace polymer-based composite materials. Lightweight epoxy-based composite materials have increasingly replaced the comparatively heavy and expensive metal alloys used in aeronautical and aerospace structural components. In particular, carbon fibers (CF)/graphene nanoplatelets (GNP)/epoxy hybrid composites can be used for this purpose owing to their high specific stiffness and strength. Therefore, this work has been completed to design, predict, and optimize the effective mechanical properties of CF/GNP/epoxy composite materials at different length scales using a multiscale modeling approach. The work-flow of modeling involves a ...


Optimization Of Shape And Control Of Linear And Nonlinear Wave Energy Converters, Jiajun Song Jan 2020

Optimization Of Shape And Control Of Linear And Nonlinear Wave Energy Converters, Jiajun Song

Dissertations, Master's Theses and Master's Reports

In this dissertation, we address the optimal control and shape optimization of Wave Energy Converters. The wave energy converters considered in this study are the single-body heaving wave energy converters, and the two-body heaving wave energy converters. Different types of wave energy converters are modeled mathematically, and different optimal controls are developed for them. The concept of shape optimization is introduced in this dissertation; the goal is to leverage nonlinear hydrodynamic forces which are dependent on the buoy shape. In this dissertation, shape optimization is carried out and its impact on energy extraction is investigated. In all the studies conducted ...


Sensor Fusion And Non-Linear Mpc Controller Development Studies For Intelligent Autonomous Vehicular Systems, Ahammad Basha Dudekula Jan 2020

Sensor Fusion And Non-Linear Mpc Controller Development Studies For Intelligent Autonomous Vehicular Systems, Ahammad Basha Dudekula

Dissertations, Master's Theses and Master's Reports

The demand for safety and fuel efficiency on ground vehicles and advancement in embedded systems created the opportunity to develop Autonomous controller. The present thesis work is three fold and it encompasses all elements that are required to prototype the autonomous intelligent system including simulation, state handling and real time implementation. The Autonomous vehicle operation is mainly dependent upon accurate state estimation and thus a major concern of implementing the autonomous navigation is obtaining robust and accurate data from sensors. This is especially true, in case of Inertial Measurement Unit (IMU) sensor data. The IMU consists of a 3-axis gyro ...


Primal-Dual 2-Approximation Algorithm For The Monotonic Multiple Depot Heterogeneous Traveling Salesman Problem, S. Rathinam, R. Ravi, J. Bae, K. Sundar Jan 2020

Primal-Dual 2-Approximation Algorithm For The Monotonic Multiple Depot Heterogeneous Traveling Salesman Problem, S. Rathinam, R. Ravi, J. Bae, K. Sundar

Michigan Tech Publications

We study a Multiple Depot Heterogeneous Traveling Salesman Problem (MDHTSP) where the cost of the traveling between any two targets depends on the type of the vehicle. The travel costs are assumed to be symmetric, satisfy the triangle inequality, and are monotonic, i.e., the travel costs between any two targets monotonically increases with the index of the vehicles. Exploiting the monotonic structure of the travel costs, we present a 2-approximation algorithm based on the primal-dual method.


A Neural Network Approach To Estimate Buoy Mooring Line Sensor Deflection, Tom Price Jan 2020

A Neural Network Approach To Estimate Buoy Mooring Line Sensor Deflection, Tom Price

Dissertations, Master's Theses and Master's Reports

Instrumented moorings are often used to measure characteristics, such as temperature and current, over the water column. However, the moorings deflect from the effects of currents and waves, which could lead to innacurate measurements. In this work, a computationally efficient method to compensate for mooring sensor position errors is developed. The two-step process first uses a hydrodynamic model of the buoy and mooring line system to create estimated mooring line deflections in a steady current. A neural network model is trained to approximate the hydrodynamic model’s mooring line displacement given the spatial location of the buoy and current profile ...


Deep Learning Of Nonlinear Dynamical System, Aditya Wagh Jan 2020

Deep Learning Of Nonlinear Dynamical System, Aditya Wagh

Dissertations, Master's Theses and Master's Reports

A data-driven approach, such as neural networks, is an alternative to traditional parametric-model methods for nonlinear system identification. Recently, long Short- Term Memory (LSTM) neural networks have been studied to model nonlinear dynamical systems. However, many of these contributions are made considering that the input to the system is known or measurable, which often may not be the case. This thesis presents a method based on LSTM for output-only modeling, identification, and prediction of nonlinear systems. A numerical study is performed and discussed on Duffing systems with various cubic nonlinearity.


Analysis Of A Circular Resonant Plate For Shock Testing, Jon Markl Jan 2020

Analysis Of A Circular Resonant Plate For Shock Testing, Jon Markl

Dissertations, Master's Theses and Master's Reports

Designing a resonant plate for shock test specifications involves an understanding of how a system will respond with a given set of input and output locations in all three directions. To investigate how to effectively change the off-axis responses to meet test specifications, a finite element model (FEM) was created and examinations of input location/angle of impact, placement of the test fixture, and placement of the impact pad were conducted. The primary tool used to determine how a structure will respond to a given input at a given output on the test structure was done using the shock response ...


Assessment And Improvement Of Computational Fluid Dynamics Methods For Separated Turbulent Flows At Low Reynolds Numbers, Tom Mancuso Jan 2020

Assessment And Improvement Of Computational Fluid Dynamics Methods For Separated Turbulent Flows At Low Reynolds Numbers, Tom Mancuso

Dissertations, Master's Theses and Master's Reports

This study investigates the accuracy of Computational Fluid Dynamics (CFD) models to predict heat transfer in turbulent separated flows at low Reynolds numbers. A novel improvement of a Scale Adaptive technique is also presented. A spectrum of turbulence models is used to simulate flow and heat transfer of two geometries; fully developed flow through a staggered tube bank and a square prism in cross flow. Experimental data for both local heat transfer and velocity data are available in the literature for these cases and have been used extensively evaluate various CFD methods. Six unsteady models were used and the results ...


Radio Frequency Studies Of Soot Loading And Ammonia Storage On A Diesel Particulate Filter With A Scr Catalyst Coating, Shreyans Sethia Jan 2020

Radio Frequency Studies Of Soot Loading And Ammonia Storage On A Diesel Particulate Filter With A Scr Catalyst Coating, Shreyans Sethia

Dissertations, Master's Theses and Master's Reports

The radio frequency (RF) measurement technique has been shown to be a viable method for measurement of the amount of soot loaded onto DPF’s [1] and the amount of NH3 stored on SCR catalysts [2]. In one of the configurations, a microwave resonant cavity is formed by the metal can encasing the enclosed catalyst. Two metal probes acting as antennas are placed on either side of the catalyst. Power transmitted between the antennas is monitored as the frequency of the signal is swept. At certain frequencies, resonance is achieved. Measurements of the resonance frequencies, amplitude at resonance, and ...


Efficient Enhancement Of Micro-Nucleation Rates In Flow-Boiling - By Concurrent Micro-Structuring Of The Boiling-Surface And Its Judicious Energization By Piezoelectric-Transducer Induced Acoustic Vibrations., Atharva Rahane Jan 2020

Efficient Enhancement Of Micro-Nucleation Rates In Flow-Boiling - By Concurrent Micro-Structuring Of The Boiling-Surface And Its Judicious Energization By Piezoelectric-Transducer Induced Acoustic Vibrations., Atharva Rahane

Dissertations, Master's Theses and Master's Reports

The report describes the science and technology backgrounds and uses for the technology breakthrough reported for enhanced flow-boiling based cooling of high-power density electronics (chips, memory etc.). A controlled but explosive growth in micro-scale nucleation rates during flow-boiling of HFE-7100 (electronics and environment friendly liquid from 3M, Inc) is enabled by the uses of inexpensive meshed-copper for micro-structuring of the boiling surface and a pair of Piezoelectric-transducers for active imposition of suitable acoustic vibrations. The pair of piezo transducers mounted just outside the mini-channel impose “in plane” acoustic vibrations of controllable amplitudes and frequencies, and they are used to induce ...


Buckling Load Study On Pop Nut (Rivet) Using Finite Element Analysis, Saurabh Shankar Shegokar Jan 2020

Buckling Load Study On Pop Nut (Rivet) Using Finite Element Analysis, Saurabh Shankar Shegokar

Dissertations, Master's Theses and Master's Reports

This study highlights the material behavior in riveting operation that includes buckling load analysis using ABAQUS. Finite Element Analysis is used to find the buckling load vs. Displacement results and validated with the results obtained in physical testing of rivet (POP Nut). A mesh sensitivity study is performed using ABAQUS to understand the optimum mesh size for this analysis. An axisymmetric model with contact properties is created and simulated to reduce the simulation time using ABAQUS. The results obtained through Finite Element Analysis show a good resemblance with the testing results. Design changes were suggested to achieve better results that ...


Active Noise Control Using Carbon Nanotube Thermophones: Case Study For An Automotive Hvac Application, Walker H. Nelson Jan 2020

Active Noise Control Using Carbon Nanotube Thermophones: Case Study For An Automotive Hvac Application, Walker H. Nelson

Dissertations, Master's Theses and Master's Reports

The goal of this project was to reduce the overall noise levels emitted by the HVAC components in a vehicle’s cabin. More specifically, the feasibility of achieving this goal using two key technologies was investigated.

The first of these technologies, Active Noise Control (ANC), is a noise attenuation technique that relies on destructive interference that “cancels” unwanted noise. Typically used in situations where physical constraints prevent passive attenuation techniques from being used, ANC is known for its high size-to-effectiveness ratio. This benefit cannot be gained without a cost however; the complexity of ANC systems is significantly higher than their ...


Generative Design In Energy Efficient Buildings, Johanna Thill Jan 2020

Generative Design In Energy Efficient Buildings, Johanna Thill

Dissertations, Master's Theses and Master's Reports

This is an investigative report on the use of generative design and genetic algorithms in the design of energy-efficient buildings. It focuses on a workflow using Project Refinery© and Dynamo© in Revit® for multi-objective optimization and visualization, and Honeybee© for daylighting analysis. The workflow was not about to run completely due to instability in Dynamo, however daylighting analysis and visualizations were produced separately from demonstrations of Refinery. It concludes that while genetic algorithms have potential to be useful in energy-efficient building design, these programs are not yet fully developed and difficult to use without extensive background knowledge and fluency in ...


Measurement Of Current Distribution In The Land Channel Direction Of A Proton Exchange Membrane Fuel Cell, Chinmay Kulkarni Jan 2020

Measurement Of Current Distribution In The Land Channel Direction Of A Proton Exchange Membrane Fuel Cell, Chinmay Kulkarni

Dissertations, Master's Theses and Master's Reports

A fully functional proton exchange membrane fuel cell with single land channel geometry on the cathode and segmented anode current collector with 9 mm2 active area with a 350μm spatial resolution was utilized to measure the local current distribution in the land channel direction. A distinguished printed circuit board approach was used for the data acquisition to adapt to any flow field design.

Performance of this segmented cell was examined at dry, wet and moderate humidity settings to study the water transport phenomenon in the PEMFC. In the dry condition at 60 ͦ C with 0% relative humidity, the non-uniform ...