Mechanical Engineering Commons^™

Designing A Cylindrical Capacitive Based Sensor For Monitoring The Table Salt’S Moisture Content During Iodization, Mwajuma Lungo

Tanzania Journal of Engineering and Technology (TJET)

Coaxial cylinder capacitive moisture sensor for determination of moisture content of table salts has been fabricated. The CMS method for determination of moisture content of table salts overcomes the effect of evaporation of iodine in table salt which results from heating in the oven drying method. The CMS overcomes the polarization effect result from the resistive methods of moisture content determination and it is non expensive to construct and it has high accuracy since measurements involves programming system in interpretation of the results. In this research, moisture content sensor based on capacitive principal created using two coaxial cylinders with height …

Renewable Energy Potential Assessment For Improving Electric Power Availability In Urban Area: A Case Of Msigani Ward In Ubungo Municipal, Tanzania, Respicius Kiiza

Tanzania Journal of Engineering and Technology (TJET)

The demand for electricity in urban areas of the developing countries like Tanzania is increasing rapidly due to factors such as increasing population, expansion of economic activities and industrialization. Msigani ward is one of the fourteen (14) administrative urban wards in Ubungo Municipal, Dar es Salaam, located at latitude 6.8031 oS and longitude 39.1188 oE. Recently, there has been observed increase in power demand in this ward. This in turn has caused a supply deficit that sometimes led to large number of interruptions caused by frequent power outage and load shedding. The total capacity of the national grid is limited …

Mppt Dc-Dc Buck-Boost Converter For Off Grid Hybrid Solar-Wind Battery System In Ikuza Island, Tanzania, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

Ikuza Island in Kagera-Tanzania faces lack of electricity due to cost challenges of extending the grid by marine cables and other transmission facilities. These makes such endeavour not appealing to the supply authority due to those higher charges. Therefore, this paper undertakes to design hybrid renewable energy sources for the island by specifically focusing on the buck-boost converter for the energy conversion from these renewable resources. The design of the bidirectional buck-boost converter for maximum power point tracking in off-grid hybrid renewable energy systems is multifaceted due to the inhomogeneity nature of the renewable energy sources. The bidirectional buck-boost converter, …

Aquaculture In Hydropower Reservoirs, Racheal Macharia

Tanzania Journal of Engineering and Technology (TJET)

There is an undoubtedly existing relationship between water, energy, and food and their interaction with the natural environment and mankind. Climate change is the talk of the day in global development discussions as it intensifies water shortages, energy, poverty, food shortages, and environmental degradation. Currently, most of the hydropower dams constructed in Africa are majorly built to store water for agricultural purposes, control flooding, and generate electricity. Notable projects include the seven forks hydropower stations located on the Tana River in Kenya; Aswan high dam in Egypt; Grand Renaissance dam in Ethiopia; Kariba dam in Zimbabwe and Akosombo in Ghana. …

Application Of Mangrove Timber In Reinforcing Concrete, John K. Makunza Jkm

Tanzania Journal of Engineering and Technology (TJET)

Use of mangrove timber beams for supporting floor slabs in historic buildings in Zanzibar Stone Town is still applied although the available structural data on mangrove timber is inadequate. This concern has called for an investigation on the structural properties of mangrove timber, so that the information obtained could help to establish the structural strength of the existing floor slabs in historic buildings. Hence, mangrove timber specimens were sampled from Zanzibar, and tested in the laboratory for their strengths in tension, compression and shear. The test results showed that mangrove is a hardwood timber of strength class D70, the highest …

Bending Performance And Failure Mechanisms Of Hybrid And Regular Sandwich Composite Structures With 3d Printed Corrugated Cores, S.Z.H. Shah, Khurram Altaf, Juhyeong Lee, Tahir Sharif, Rizwan Saeed Choudhry, S. M. Hussain

Mechanical and Aerospace Engineering Faculty Publications

The effect of core geometry and hybridization on the bending performance and failure mechanisms of carbon fibre-reinforced polymer (CFRP) and glass fibre-reinforced polymer (GFRP) corrugated sandwich composite structures (SCS) were experimentally investigated using a three-point bend test. The CFRP and GFRP corrugated cores and facesheets were produced using Fused Filament Fabrication (FFF) and vacuum-assisted infusion processes, respectively. Three types of corrugated SCSs were built: SCSs with different core geometries (circular, square, trapezoidal, sinusoidal, and triangular), hybrid SCSs with different CFRP and GFRP cores and facesheets, and fully 3D-printed CFRP and GFRP SCSs. The corrugated SCS with square core geometry outperformed …

From A Single Grain To Microstructure: How Explosive Grains Interact Under Shock Compression, Lawrence Salvati, Siva Kumar Valluri, Dana D. Dlott

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We studied the effect of varying the HMX concentration in a plastic-bonded explosive (PBX) by analyzing the time-dependent thermal emission with short (4 ns) duration shocks that produced pressures of about 20 GPa. We found that the HMX tended to aggregate even at the lowest concentrations. Once the cluster size reached about 15 μm, at 30 wt.%, the cluster size started increasing more dramatically, but energy release during deflagration reached a plateau. These observations are consistent with the idea that the clusters act as a limiting factor for hot spot criticality, possibly due to heat loss mechanisms such as conduction …

Porosity: The Key To Initiating Metallic Composite Particles Under Shock Compression, Siva Kumar Valluri, Edward L. Dreizin, Dana D. Dlott

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The use of metallic composites as additives can potentially improve the energy density of explosives. Before employing them as additives it is imperative to design composites with physically separated metal fuel and oxidizer that can combust on short time scales, tens of nanoseconds, similar to high-performance molecular explosives. Towards that end, sensitizing composite powder particles to shock compression is crucial. In the current work, particle porosity is explored as means to induce hotspot formation within the particle through pore-collapse. Particles of two porous powders, Al-MoO3-KNO3 (equivalence ratio 3) and Al-CuO (equivalence ratio 4) prepared by arrested reactive milling with emulsion …

Seeing Inside Shocked Plastic-Bonded Explosives, Dhanalakshmi Sellan, Lawrence Salvati, Siva Kumar Valluri, Dana D. Dlott, Xuan Zhou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A new method is described to study how microstructures within a plastic-bonded explosive (PBX) interact with shock waves to produce hot spots, and to identify the critical hot spots that grow into a deflagration. A unique feature of this method is that it allows us to see every crystal in the PBX during the shock. We used an HMX-based PBX fabricated into a wafer about one crystal thick so there are no crystals hidden from view. The wafer is embedded in a transparent polymer in a traveling wave geometry, and a microscope with a laser flyer launcher and a nanosecond …

Numerical Study Of Solar Receiver Tube With Modified Surface Roughness For Enhanced And Selective Absorptivity In Concentrated Solar Power Tower, Shawn Hatcher, Mathew Z. Farias, Jianzhi Li, Peiwen Li, Ben Xu

Manufacturing & Industrial Engineering Faculty Publications

Concentrated solar power (CSP) is a reliable renewable energy source that is progressively lowering its cost of energy. However, the heat loss due to reflected and emitted radiation hinders the maximum achievable thermal efficiency for solar receiver tubes on the solar tower. Current solar selective coatings cannot withstand the high temperatures that come with state-of-the-art CSP towers often needing to be recoated soon after initial operation. We intend to use Inconel 718 with different additive manufacturing (AM) practices to construct surfaces that allow for more light-trapping to occur. By adjusting printing parameters, we can tailor a surface to allow for …

Sustainability Matchmaking: Exploration Into Using Excess Renewable Energy To Deliver ‘Free’ Energy To Fuel Poor Homes – A Preliminary Case Study In Ireland, Ciara Ahern, Ronan Oliver

Articles

The aggregated fuel cost of domestic hot water (DHW) generation in Ireland, in 2022, was €529M with associated emissions/load of 1.3MtCO₂/289GWh. The shadow price of carbon monetises the negative impact of emissions, rising with time; DHW generation has an associated shadow carbon cost of €13M in 2022, rising to €42M in 2030 and €335M in 2050.

In 2020, c12%/€441M of wind was curtailed or wasted as inter alia, there was no demand at times of high wind. Meanwhile, a ‘silent crisis’ is occurring in Ireland wherein one-in-two dwellings were considered in fuel poverty in 2022. Households in …

Evaluation Of Digital Twin Approaches For Thermal Modeling And Energy Optimization For Existing Buildings, Jason Bastie Muermann

Theses and Dissertations

Residential, commercial, and industrial building sectors in the United States were responsible for 42% of the nation’s consumption of 100.2 quadrillion BTUs of energy in 2019 [1]. 80% of the nation’s energy is sourced from fossil fuels, including coal, natural gas, and petroleum. Fossil fuels are known contributors to carbon emissions and climate change, making energy reduction vital. Consequently, New Jersey Department of Military and Veterans Affairs (NJDMAVA) is tasked with evaluating energy consumption and efficiency in all New Jersey Army National Guard (NJARNG) facilities, as mandated by TAG Policy Letter 18-5, Executive Order 13990, and the Energy Independence and …

Fatigue Behavior Of Cu-Zr Metallic Glasses Under Cyclic Loading, Nikolai Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of oscillatory shear deformation on the fatigue life, yielding transition, and flow localization in metallic glasses is investigated using molecular dynamics simulations. We study a well-annealed Cu-Zr amorphous alloy subjected to periodic shear at room temperature. We find that upon loading for hundreds of cycles at strain amplitudes just below a critical value, the potential energy at zero strain remains nearly constant and plastic events are highly localized. By contrast, at strain amplitudes above the critical point, the plastic deformation is gradually accumulated upon continued loading until the yielding transition and the formation of a shear band across …

Dynamic Skin Strain Fields In The Lumbar Region During Functional Movement, Andrew Gibbons, Anton Bowden, Ulrike H. Mitchell, David T. Fullwood

Student Works

Increasing efforts to leverage skin mounted wearables has exposed a gap in our understanding of skin strain in the lumbar region. Lumbar skin is known to be both inhomogenous and anisotropic, and experiences dramatic material strain during activities of daily living (ADLs). Previous efforts to quantify strain fields during ADLs has been limited to a few activities (primarily flexion) and have neglected inhomogeneity or anisotropy. The purpose of the present work was to address this gap by measuring large-deformation skin strain tensors in healthy volunteers during a cadre of functional movements.

36 tightly packed retro-reflective markers were mounted to the …

Trumpet Directivity From A Rotating Semicircular Array, Samuel D. Bellows, Joseph E. Avila, Timothy W. Leishman

Directivity

The directivity function of a played musical instrument describes the angular dependence of its acoustic radiation and diffraction about the instrument, musician, and musician’s chair. Directivity influences sound in rehearsal, performance, and recording environments and signals in audio systems. Because high-resolution, spherically comprehensive measurements of played musical instruments have been unavailable in the past, the authors have undertaken research to produce and share such data for studies of musical instruments, simulations of acoustical environments, optimizations of microphone placements, and other applications. The authors acquired the data from repeated chromatic scales produced by a trumpet played at mezzo-forte in an anechoic …

Electric Motor And Transmission Integration For Light-Duty Electric Vehicles: A 2023 Benchmarking Perspective And Component Sizing For A Fleet Approach, Darrell Robinette

Michigan Tech Publications

A review of past, current, and emerging electric vehicle (EV) propulsion system technologies and their integration is the focus of this paper, namely, the matching of electric motor (EM) and transmission (TRM) to meet basic requirements and performance targets. The fundaments of EM and TRM matching from a tractive effort and a vehicle dynamics perspective are provided as an introductory context to available or near-production propulsion system products available from OEM and Tier 1 suppliers. Engineering data and details regarding EM and TRM combinations are detailed with a specific focus on volumetric and mass density. Evolutionary trends in EM and …

Stomatal Opening Efficiency Is Controlled By Cell Wall Organization In Arabidopsis Thaliana, Sedighe Keynia, Leila Jaafar, You Zhou, Charles T. Anderson, Joseph A. Turner

Department of Mechanical and Materials Engineering: Faculty Publications

Stomatal function in plants is regulated by the nanoscale architecture of the cell wall and turgor pressure, which together control stomatal pore size to facilitate gas exchange and photosynthesis. The mechanical properties of the cell wall and cell geometry are critical determinants of stomatal dynamics. However, the specific biomechanical functions of wall constituents, for example, cellulose and pectins, and their impact on the work required to open or close the stomatal pore are unclear. Here, we use nanoindentation in normal and lateral directions, computational modeling, and microscopic imaging of cells from the model plant Arabidopsis thaliana to investigate the precise …

A Facile Graphene Conductive Polymer Paper Based Biosensor For Dopamine, Tnf-Α, And Il-6 Detection, Md Ashiqur Rahman, Ramendra Kishor Pal, Nazmul Islam, Robert Freeman, Francois Berthiaume, Aaron Mazzeo, Ali Ashraf

Mechanical Engineering Faculty Publications

Paper-based biosensors are a potential paradigm of sensitivity achieved via microporous spreading/microfluidics, simplicity, and affordability. In this paper, we develop decorated paper with graphene and conductive polymer (herein referred to as graphene conductive polymer paper-based sensor or GCPPS) for sensitive detection of biomolecules. Planetary mixing resulted in uniformly dispersed graphene and conductive polymer ink, which was applied to laser-cut Whatman filter paper substrates. Scanning electron microscopy and Raman spectroscopy showed strong attachment of conductive polymer-functionalized graphene to cellulose fibers. The GCPPS detected dopamine and cytokines, such as tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6) in the ranges of 12.5–400 …

Wire Deflection Investigation During Wedm Of Aisi 304 Stainless Steel: An Experimental And Numerical Study, Sara A. El-Bahloul, Mohamed G. Elkhateeb

Mansoura Engineering Journal

Wire electrical discharge machining (WEDM) is a specific form of electrical discharge machining that employs a small diameter wire electrode to cut a narrow kerf in the workpiece. Since the wire deflection has a negative effect on the performed cutting, this research seeks to study the resultant wire deflection during WEDM of AISI 304 stainless steel. This study is performed with the help of three types of modeling; namely, mathematical modeling, experimental modeling, and thermo-mechanical finite element modeling. The mathematical modeling is performed to analyze the stresses and the wire lag, while the experimental modeling is achieved to observe the …

A General Effectiveness-Ntu Modeling Framework For Membrane Dehumidification Systems, Andrew J. Fix, James E. Braun, David M. Warsinger

School of Mechanical Engineering Faculty Publications

Selective membrane dehumidification is a promising technology for energy efficient air dehumidification in buildings and has been ranked as a top alternative technology by the Department of Energy. One critical area that needs to be addressed is system modeling that incorporates device mass transfer characteristics and sizing. This work develops, validates, and applies a simple effectiveness-number of transfer units (𝜀−𝑁TU) modeling framework for dehumidification technologies that can be used to predict performance and determine required membrane area for a wide range of technologies, including energy recovery ventilators, vacuum membrane dehumidification, and desiccant dehumidifiers. Although the 𝜀−𝑁TU method is a well-established …

A Numerical Investigation Realizing The Flow Structure And Heat Transfer Performance Of The Potential Impinging Jets, Mohammed Sami Uddin Khan

Thesis/ Dissertation Defenses

The demand for improvement in the performance of gas turbines has led to the consideration of flows at increasingly high temperatures, but this introduces challenges in terms of maintaining their structural integrity and preventing overheating. To respond to these challenges, gas turbine manufacturers have turned to internal cooling, and jet impingement provides an effective solution for cooling the leading edge of the blades of gas turbines. In this study, the author numerically simulated the cooling performance of the leading edge of the blades of a gas turbine under constant heat flux by using five configurations of jet impingement: a steady …

Laboratory Glovebox, Jackson T. Tenne, Noah Fitzgerald, Scott Stirling, Danny Ho

Mechanical Engineering

The Laboratory Glovebox project aimed to create an affordable, functional, ready to use, airtight workstation enabling Dr. Ramanan Sritharan to continue his research of the mechanical properties of nanomaterials. When airborne, nanomaterials are a health risk if inhaled, so the design requires a hermetic seal to protect the user. The design was meant to emulate features of the glovebox used by Dr. Sritharan during his PhD research, but was optimized to meet a budget of $3000, much cheaper than comparable alternatives. Key design features included acrylic panels, a transfer chamber, glove mounts, and a main access door, all sealed to …

Computation Of High-Order Sensitivities Of Model Responses To Model Parameters—I: Underlying Motivation And Current Methods, Dan Gabriel Cacuci

Faculty Publications

The mathematical/computational model of a physical system comprises parameters and independent and dependent variables. Since the physical system is seldom known precisely and since the model’s parameters stem from experimental procedures that are also subject to uncertainties, the results predicted by a computational model are imperfect. Quantifying the reliability and accuracy of results produced by a model (called “model responses”) requires the availability of sensitivities (i.e., functional partial derivatives) of model responses with respect to model parameters. This work reviews the basic motivations for computing high-order sensitivities and illustrates their importance by means of an OECD/NEA reactor physics benchmark, which …

Computation Of High-Order Sensitivities Of Model Responses To Model Parameters—Ii: Introducing The Second-Order Adjoint Sensitivity Analysis Methodology For Computing Response Sensitivities To Functions/Features Of Parameters, Dan Gabriel Cacuci

Faculty Publications

This work introduces a new methodology, which generalizes the extant second-order adjoint sensitivity analysis methodology for computing sensitivities of model responses to primary model parameters. This new methodology enables the computation, with unparalleled efficiency, of second-order sensitivities of responses to functions of uncertain model parameters, including uncertain boundaries and internal interfaces, for linear and/or nonlinear models. Such functions of primary model parameters customarily describe characteristic “features” of the system under consideration, including correlations modeling material properties, flow regimes, etc. The number of such “feature” functions is considerably smaller than the total number of primary model parameters. By enabling the computations …

Optimizing Mn-Al Permanent Magnet Performance Through Control Of The Phase Transformation, Ternary Element Addition, And Advanced Processing, Thomas R. Keller

Dartmouth College Ph.D Dissertations

The growing need for electrical power in machines and vehicles brings with it a growing need for critical materials. The current high-performance permanent magnets (PMs) based on rare-earth (RE) elements Nd and Sm cannot escape the problem of raw material cost, geographic scarcity in the earth’s crust, and lack of circular global supply chains. This poses a problem of industrial ecology: can PMs be made from inexpensive, more abundant materials while still meeting sufficient performance criteria? PMs based on the magnetic τ phase of Mn-Al offer a possible alternative to REPMs. However, years of innovation have not yet achieved real-world …

Modeling Yield Strength Of Austenitic Stainless Steel Welds Using Multiple Regression Analysis And Machine Learning, Sukil Park, Myeonghwan Choi, Dongyoon Kim, Cheolhee Kim, Namhyun Kang

Mechanical and Materials Engineering Faculty Publications and Presentations

Designing welding filler metals with low cracking susceptibility and high strength is essential in welding low-temperature base metals, such as austenitic stainless steel, which is widely utilized for various applications. A strength model for weld metals using austenitic stainless steel consumables has not yet been developed. In this study, such a model was successfully developed. Two types of models were developed and analyzed: conventional multiple regression and machinelearning- based models. The input variables for these models were the chemical composition and heat input per unit length. Multiple regression analysis utilized five statistically significant input variables at a significance level of …

Me-Em Enewsbrief, June 2023, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Non-Planar 3d Printing Of Thermosetting Prepolymers, Junaid Abid Ali

Master's Theses

Additive manufacturing or three-dimensional (3D) printing is an advanced process of manufacturing that challenges traditional manufacturing methodologies. However, the current 3D printing process does exhibit specific limitations. It generates printing paths that are in a horizontal plane, proving inadequate for printing curved or non-flat structures. This study established a printing procedure capable of simultaneously executing printing in X, Y, and Z directions. The limitations posed by conventional 3D printing lead to the poor surface quality of curved printed objects. In contrast, non-planar 3D printing provides smoother surfaces. This work developed a program capable of producing non-planar print paths for the …

Role Of Binder On Yield Strength Of Polycaprolactone/Dimethylsulfone Composites For Bio-Applications, Kyung-Eun Min, Jae-Won Jang, Sung Yi, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

Polycaprolactone (PCL) and dimethylsulfone (DMSO2) composites can tailor the properties of scaffold materials, allowing their use in bone tissue engineering. With an increase in DMSO2 content, the modulus of the material increases but not the yield strength. In order to increase yield strength, a binder was added. However, the optimization of the content and the mixing process of the binder were not optimized in the previous studies. In this study, gamma-methacryloxypropyltrimethoxysilane (A-174) was used as a binder to increase the strength of a composite. Four different mixing processes were employed based on the binder mixing sequence. The binders with content …

Modeling The Moisture Content And Drying Rate Of Zucchini (Cucurbita Pepo L.) In A Solar Hybrid Dryer Using Ann And Anfis Methods, Halil Nusret Bulus, Aytac Moralar, Soner Celen

The Philippine Agricultural Scientist

Estimating product drying kinetics is critical to obtain the best drying process without compromising product quality and necessitates the development of numerical drying models. This research aims to compare the prediction models developed using artificial neural network (ANN) and adaptive network-based fuzzy inference system (ANFIS), two popular machine learning approaches in the recent years. Zucchini slices were chosen as samples and dried in a solar-assisted microwave belt dryer at 0.245 m/min belt speed and microwave powers of 0.7, 1, and 1.4 kW. On the data set obtained by computing the moisture content and drying rate values, prediction models were developed …