Mechanical Engineering Commons^™

Quantification Of Heat Flows Through Building Entrance Doors On A Winter Day, Daeho Kang

Publications and Research

The current methods for the prediction of the heat flow through building entrance doors have been used for years while involved with a certain degree of uncertainty. This paper describes an experimental method that accurately quantified such heat flow. The experiment monitored local environmental parameters in a college building on a cold winter day. The results of the experiment demonstrated that the experimental method is viable to accurately estimate the heat flow throughout the entrance doors and the presence of a vestibule moderated heat losses from the conditioned area. The results will be used for validating the existing methods.

Aircraft Hydraulic Systems - Fundamentals, Nihad E. Daidzic

Aviation Department Publications

Aircraft hydraulic systems are essential non-propulsive power systems. Hydraulic power systems are used to power major functional aircraft systems, such as flight controls (primary and secondary), friction braking, nose gear steering, thrust-reversers, operating heavy cargo doors, etc.

A Techno-Economic Analysis Of Current Cooling Techniques In Irish Data Centres, Lee Gibbons, Bryan Coyne, David Kennedy, Sajad Alimohammadi

Articles

This research is part of a comprehensive study to determine reformative actions for cooling regimes within the Irish data centre market. To achieve this goal, preliminary Exergy, Entropy change and operational cost analyses are used. It is determined that there is no clear advantage for using one cooling method over another without knowing the data centres secondary function (e.g. district heating, energy generation). Air cooling technology is a good candidate for a highly reliable system due to the low exhaust temperatures of 30°C. Two-phase immersion is a possibility for economically viable data centres where operational costs are to be minimised, …

Strong Circular Dichroism In Chiral Plasmonic Metasurfaces Optimized By Micro-Genetic Algorithm, Zhigang Li, Daniel Rosenmann, David A. Czaplewski, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Strong circular dichroism in absorption in the near-infrared wavelength range is realized by designing binary-pattern chiral plasmonic metasurfaces via the micro-genetic algorithm optimization method. The influence of geometric parameter modifications in the binary-pattern nanostructures on the circular dichroism performance is studied. The strong circular dichroism in absorption is attributed to the simultaneous excitation and field interference of the resonant modes with relative phase delay under linearly polarized incident light. This work provides a universal design method toward the on-demand properties of chiral metasurfaces, which paves the way for future applications in chemical and biological sensing, chiral imaging and spectroscopy.

The Influence Of Temperature On Dispersion Of Particles On Liquid Surfaces, Sathish Kumar Gurupatham, Valmiki Sooklal, A. Hensen, M. Conner

Faculty Articles

It was shown recently that small particles and powders spontaneously disperse on liquid surfaces when they come in contact with the interface for the first time (Figure 2). This happens due to the combined effect of the capillary force, buoyant weight of the particle and the viscous drag that the particles experience when they encounter the liquid surface. The particles undergo oscillations normal to the interface before they come to the equilibrium position on the interface. These oscillations, in turn, induce a flow on the interface which disperses the particles radially outward. This phenomenon has a significant role in the …

Mechanical And Temperature Resilience Of Multi-Material Systems For Printed Electronics Packaging, Clayton Neff, Justin Nussbaum, Chris Gardiner, Nathan B. Crane, James L. Zunino, Mike Newton

Faculty Publications

In this work, two AM technologies were utilized to compare the effectiveness of fabricating a simple electronic device with a conductive trace and hollow cylinder representative of ‘printed packaging’ that would survive harsh environmental conditions. The printed packaging cylinder delineates printed potting for electronics packaging. An nScrypt direct write (DW) system was the primary manufacturing system but a developing technology—coined large area projection sintering (LAPS)—manufactured a subset of samples for comparison. The tests follow Military Standard (MIL STD) 883K and include resiliency evaluation for die shear strength, temperature cycling, thermal shock, and high G loading by mechanical shock. Results indicate …

Rare But Conceivable: Determining The Likelihood Of Meteors And Other Infrequent Events, Michael S. Schmidt, Maria Vega-Westhoff

Engineering Management and Systems Engineering Faculty Research & Creative Works

In the aftermath of a rare but devastating disaster, there is a tendency to overestimate how frequent such an event may be, hence a tendency to overestimate the risk associated with such an event. Those concerned with process safety will acknowledge that though rare, events like meteors, hurricanes, and airplane crashes that can impact chemical plants are conceivable. Typically, though, they have nothing more than feelings to decide whether these events are likely enough to be considered "credible." This compiles data from the literature for several "meteors," both natural and man-made, that often become a cause of general concern after …

Reliability-Based Design Optimization Of Load Sharing Systems Using Ssi-Markov Models, Arun Bala Subramaniyan, Rong Pan, Xiaoping Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents a novel single loop approach to design the components of the load sharing systems by optimally allocating the failure probabilities to each component, thereby satisfying the overall system reliability requirement. The Reliability–Based Design Optimization (RBDO) of load sharing systems is computationally intensive due to the dynamic nature of component failure probabilities, since the failure of one component will vary the failure probabilities of other working components. Many RBDO methods have been successfully utilized to design individual components, however using these methods for handling system level reliability constraints is still a challenging task. This is because of a …

Sensor Development To Utilize Underwater Electric Potential (Uep) Fields To Navigate The Underwater Areas Of Ship Hulls, Caglar Erdogan

Link Foundation Ocean Engineering and Instrumentation Fellowship Reports

Underwater electric potential fields occur due to natural reasons, such as changes in atmosphere, ionosphere, magnetosphere, and movements of water bodies in the ocean, or artificial reasons, such as stray and controlled electric currents, or both. Electric potential fields around ship hulls are mainly generated due to corrosion protection systems and dissimilar materials. The electric field intensity over an impressed current anode of a large cruise ship operating in with seawater with a resistance of 20 0-cm is around 90 mV/cm, whereas it is between 0.4 and 1 mV/cm on a propeller for the same ship. The theoretical field intensities …

Pairing Electrostatic Levitation With Triboelectric Transduction For High-Performance Self-Powered Mems Sensors And Actuators, Mark Pallay, Alwathiqbellah I. Ibrahim, Ronald N. Miles, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

We demonstrate that an electrostatic levitation MEMS switch can be operated by applying mechanical pres- sure to a triboelectric generator. The toggling mechanism of the switch draws no current but requires a high actuating voltage, while the generator can supply a high voltage but only produces microwatts of power. The synergistic combination results in an entirely self-powered sensor and switch; the normally-closed MEMS switch can be toggled open by applying a threshold force to the generator without the need for any outside power or supplementary circuitry. A model of the MEMS switch and electrostatic force is validated with experimental data. …

Me-Em Enewsbrief, September 2019, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Synthesis Of Multiwall Α-Fe2o3 Hollow Fibers Via A Centrifugal Spinning Technique, Mandana Akia, K. A. Mkhoyan, Karen Lozano

Mechanical Engineering Faculty Publications

Highlights

• Hollow hematite (α-Fe2O3) fine fibers were fabricated via a simple, flexible, and scalable technique.

• An aqueous solution with iron precursor/polymer was used in the centrifugal spinning process

• Developed fibers show average wall thickness of 55 ± 15 nm and outer fiber diameter of 852 ± 86 nm

Abstract

Hollow hematite (α-Fe2O3) fine fibers with multiwall structure were synthesized by utilizing a centrifugal spinning technique. Aqueous solutions of polyvinyl pyrrolidone and iron (III) nitrate nonahydrate were prepared and spun into fibers. The precursor fibers were heat treated at 650 °C to form iron oxide fibers. Scanning electron micrographs revealed the …

Data Multiplexing In Vector Acoustic Communication: System Design And Experiments, Erjian Zhang

Dissertations

Acoustic particle velocity channels, which are vector components of the acoustic field, have been recently explored to achieve communication purposes underwater. Vector sensors and transducers that can utilize acoustic particle velocity channels have compact multichannel designs, which are perfect for compact size underwater platforms. In this dissertation, an underwater acoustic multiple-input multiple-output (MIMO) communication system featuring orthogonal frequency division multiplexing (OFDM) and frequency shift keying (FSK) modulation is discussed. By transmitting multiple independent data streams simultaneously over several channels within the same bandwidth, the proposed MIMO system increases the transmission rate. A variety of components of the system such as …

Evaluating The Rheological And Tribological Behaviors Of Coconut Oil Modified With Nanoparticles As Lubricant Additives, Vicente Cortes, Javier A. Ortega

Mechanical Engineering Faculty Publications

In metal-forming processes, the use of lubricants for providing desirable tribological conditions at the tool–workpiece interface is critical to increase the material formability and prolonging tool life. Nowadays, the depletion of crude oil reserves in the world and the global concern in protecting the environment from contamination have renewed interest in developing environmentally-friendly lubricants derived from alternative sources such as vegetable oils. In the present study, the rheological and tribological behavior of coconut oil modified with nanoparticle additives was experimentally evaluated. Two different nanoparticle additives were investigated: Silicon dioxide (SiO₂) and copper oxide (CuO). For the two conditions, …

Measurement Of Stresses And Their Effect On Transport In Thin Film Battery Electrodes, Subhajit Rakshit

Dissertations

At the moment, there is a significant push towards environmentally friendly energy production and gasoline-free transportation technologies. As a result, there is a renewed interest in energy storage devices such as lithium-ion batteries which will play a key role in providing energy storage capability for these applications. However, the current battery technology is reaching its limits and may not meet future energy storage demands. The increased demand and the limited lithium reserves in geographically remote areas of the earth will lead to higher cost of Li. The alternative battery technologies, such as sodium-ion batteries, are promising due to their low …

Aerodynamic Centers Of Arbitrary Airfoils Below Stall, Douglas F. Hunsaker, Orrin D. Pope, Jeffrey D. Taylor, Josh Hodson

Mechanical and Aerospace Engineering Student Publications and Presentations

The aerodynamic center of an airfoil is commonly estimated to lie at the quarter-chord. This traditional estimate is based on thin airfoil theory, which neglects aerodynamic and geometric nonlinearities. Even below stall, these nonlinearities can have a significant effect on the location of the aerodynamic center. Here, a method is presented for accurately predicting the aerodynamic center of any airfoil from known lift, drag, and pitching-moment data as a function of angle of attack. The method accounts for aerodynamic and geometric nonlinearities, and it does not include small-angle, small-camber, and thin-airfoil approximations. It is shown that the aerodynamic center of …

Initial Development Of A Prototype Sensor Testbed For Fetal Monitoring, Christian Beauvais

Theses and Dissertations

The objective of this research is to design and manufacture a device that exhibits some of the bio-physiological signals relevant to fetal health monitoring. Currently, limited options exist for testing the performance of monitoring devices such as the tocodynamometer (TOCO) and electrocardiograph (ECG) that measure the bio-physiological signals of a woman and her fetus. Sensor designers need ways of generating and acquiring signals that do not carry the ethical burden of human testing. The development of such a device, as considered in this work, may involve using muscle wire or an inflatable tube as prospective foundations for simulating uterine contraction. …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Undergraduate Researcher Awarded at Georgia Environmental Conference

Understanding Of The Ship Design Energy Efficiency And Its Implications In Practice, Haichao Yuan

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

How Will Climate Alter Efficiency Objectives? Simulated Impact Of Using Recent Versus Historic European Weather Data For The Cost-Optimal Design Of Nearly Zero Energy Buildings (Nzebs), Florida Solar Energy Center, Delia D'Agostino

FSEC Energy Research Center®

Achieving "nearly zero energy buildings" (NZEB) has been established as a vital objective over the next decade within the European Union (EU) [1, 2]. Previous work has shown that a series of very cost-effective thermal efficiency measures, equipment, appliance and renewable energy choices are available across climates to reach the NZEB objective. Resulting detailed energy and economic optimization findings have been obtained and published. One area that has just begun to be explored, however, is how selection of weather files and their application against coming climate change can influence outcomes from energy optimization procedures.

Presented at: CLIMA 2019, REHVA 13th …

An Optical-Based Technique To Obtain Vibration Characteristics Of Rotating Tires, Aakash Mange, Theresa Atkinson, Jennifer Bastiaan, Javad Baqersad

Mechanical Engineering Publications

The dynamic characteristics of tires are critical in the overall vibrations of vehicles because the tire-road interface is the only medium of energy transfer between the vehicle and the road surface. Obtaining the natural frequencies and mode shapes of the tire helps in improving the comfort of the passengers. The vibrational characteristics of structures are usually obtained by performing conventional impact hammer modal testing, in which the structure is excited with an impact hammer and the response of the structure under excitation is captured using accelerometers. However, this approach only provides the response of the structure at a few discrete …

Docking Control Of An Autonomous Underwater Vehicle Using Reinforcement Learning, Enrico Anderlini, Gordon Parker, Giles Thomas

Michigan Tech Publications, Part 1

To achieve persistent systems in the future, autonomous underwater vehicles (AUVs) will need to autonomously dock onto a charging station. Here, reinforcement learning strategies were applied for the first time to control the docking of an AUV onto a fixed platform in a simulation environment. Two reinforcement learning schemes were investigated: one with continuous state and action spaces, deep deterministic policy gradient (DDPG), and one with continuous state but discrete action spaces, deep Q network (DQN). For DQN, the discrete actions were selected as step changes in the control input signals. The performance of the reinforcement learning strategies was compared …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Math Review Sessions

Non-Contact Distillation, Rawand Muzafar Rasheed

Dissertations and Theses

Leidenfrost phenomenon has been studied extensively for its role in applications ranging from nuclear reactor cooling, to metals manufacturing, combustion, and other fields. Herein, Leidenfrost phenomenon is pursued towards non-contact distillation processes with hopes of reducing or even eliminating contaminant fouling. In particular, the microgravity environment of a drop tower is exploited to demonstrate the facility with which droplets achieve and sustain the Leidenfrost state. Dynamic Leidenfrost impacts in microgravity are presented for impacts on hydrophilic and superhydrophobic planar substrates, macro-pillar arrays, confined passageways, and others. Nearly ideal elastic non-contact impacts and droplet oscillation modes are observed. Dynamic Leidenfrost impacts …

Experimental Evaluation Of Self-Expandable Metallic Tracheobronchial Stents, Yanli Wang, Pengfei Dong, Jingyao Ke, Xiang Shen, Zongming Li, Kewei Ren, Xinwei Han, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

The self-expandable metallic stents have been widely used in tracheobronchial obstruction or fistulation, including the J-shaped and Y-shaped stents, named after the shape of the branch-stem junction of the stent. However, there is scarce data on the mechanical performance of these tracheobronchial stents, which is essential for optimal stent implantation. In this work, eight self-expandable metallic tracheobronchial stents in three types (i.e., straight, J-shaped, and Y-shaped), with or without cover, were characterized. The compression resistance of the stems was investigated through both compression and indentation tests. The bending resistance of the branches in the J-shaped and Y-shaped stents was assessed …

Tribological And Thermal Transport Performance Of Sio2-Based Natural Lubricants, Jaime Taha-Tijerina, Karla Aviña, Jose Manual Diabb

Informatics and Engineering Systems Faculty Publications

Fluids and lubricants are critical for the mechanical manufacturing processing of metals, due to a high amount of friction generated, also reflected as heat, could wear and damage tooling and machine components. The proper application of lubricants increases machinery lifetime, decreases long-term costs, and energy and time consumption due to the maintenance or components exchange/repairs. Besides being non-renewable, mineral oils bring consequences to the environment due to their low biodegradability and could affect the user with respiratory and skin diseases. Recently, due to an increase in environmental awareness, the search of biocompatible and efficient lubricants has become a technology goal. …

Interface Effects On He Ion Irradiation In Nanostructured Materials, Wenfan Yang, Jingyu Pang, Shijian Zheng, Jian Wang, Xinghang Zhang, Xiuliang Ma

Department of Mechanical and Materials Engineering: Faculty Publications

In advanced fission and fusion reactors, structural materials suffer from high dose irradiation by energetic particles and are subject to severe microstructure damage. He atoms, as a byproduct of the (n) transmutation reaction, could accumulate to form deleterious cavities, which accelerate radiation-induced embrittlement, swelling and surface deterioration, ultimately degrade the service lifetime of reactor materials. Extensive studies have been performed to explore the strategies that can mitigate He ion irradiation damage. Recently, nanostructured materials have received broad attention because they contain abundant interfaces that are efficient sinks for radiation-induced defects. In this review, we summarize and analyze the current understandings …

Design, Development And Implementation Of An Electrical Controller For A Solar-Electrical Collector, Sahar Mahboob, Razieh Pourdarbani, Bahman Behfar, Hossein Behfar

Emirates Journal for Engineering Research

Todays, maintaining atmospheric health is one of the most important prerequisites for sustainable global economic development, and the international community has no choice but to switch to renewable energies, including solar energy. The goal of the study was to provide a temperature of 60 ° C for drying summer fruits such as apricots therefore we investigated the effect of temperature control systems on the solar-electrical collector performance. Three LM35 temperature sensors were placed at 3 points of the collector (before the air inlet to the collector, after the air outlet from the collector and after heating elements) that were linked …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• Undergraduate Student Wins Award in Internal Combustion Engine Division Competition

Applications Of Laser Machining For Fiber Optic Sensor Development, Lauren Sailor

The Journal of Purdue Undergraduate Research

No abstract provided.