Mechanical Engineering Commons^™

Product Design For Children With Limb Defects, Cecilee Petersen, Richard Fry

Journal of Undergraduate Research

Congenital Limb Deficiency (CLD) occurs when a fetus’s upper or lower limbs do not form completely during pregnancy. This project analyzes how girls aged seven to thirteen years with upper-limb CLD adjust to daily tasks and supports the design of a mechanism to help them perform a specific activity independently. Early research became the foundation for a case study of an eight-year old girl named Ava. Ava was born with only one elbow-length cleft hand on her right side and one finger connected to her left shoulder joint . She learns to use her “nubs” effectively for most tasks, such …

Does Hypochlorous Acid Accelerate The Degradation Of Absorbable Sutures, Stephen Pinnock, Anton Bowden

Journal of Undergraduate Research

Patients who undergo surgery may experience infection in the surgical site due to bacteria with a biofilm phenotype. This biofilm can render the bacteria resilient to standard antibiotics and the wound must be disinfected with an antimicrobial solution. Hypochlorous acid (HOCl) is a commonly used surgical antimicrobial used to disinfect these surgical sites. However, there is uncertainty as to whether the HOCl affects the stiffness and strength of the remaining sutures. These sutures are typically absorbable and need to maintain their integrity for the wound to heal properly. The purpose of this mentored research was to determine the effects of …

Passive Cubesat Probes For Affordable, Low-Risk Inspection Of Space Vehicles, Josh Cannon, Brian Iverson

Journal of Undergraduate Research

Effective fault detection is vital for safe and reliable spacecraft performance. Traditionally, developers have relied almost exclusively on on-board instrumentation to detect faults in spacecraft performance. Remote inspection can provide a holistic complement to on-board instrumentation, but it is seldom incorporated into spacecraft missions due to its cost and risk. As a result, multiple spacecraft have been lost due to unchecked faults in areas without instrumentation.

Quantifying The Friedreich Ataxia Rating Scale And The Functional Performance Measures, Chelsea Rene Davis

USF Tampa Graduate Theses and Dissertations

Friedreich Ataxia (FA) is a debilitating autosomal-recessive neurodegenerative disorder which is characterized by ataxia of all four limbs, difficulty walking, areflexia, and dysarthria. Further complications of FA include diabetes, scoliosis, and hypertrophic cardiomyopathy. Approximately three-quarters of people with FA have onset before the age of 25 and in most instances, affected individuals will require the use of a wheelchair within ten years after symptoms emerge.

The current advancements in clinical trials have escalated the developmental demand for a scale which validates adjustments in FA. The Friedreich Ataxia Rating Scale (FARS) is a disease-specific semi-qualitative assessment which includes three subscales (functional …

Impact Of Micro- And Nano-Structured Surfaces On Condensation Heat Transfer Effectiveness, D. Jacob Butterfield, Dr. Brian Iverson

Journal of Undergraduate Research

This paper reports observations from condensation heat transfer tests performed on superhydrophobic (water-repelling) surfaces. Condensation is used in heat transfer applications ranging from industrial power generation to desalination. Superhydrophobic surfaces have been discovered to increase the effectiveness of this heat transfer process by increasing water droplet mobility. This project was concerned with quantifying the ability of superhydrophobic surfaces to increase the rate of heat transfer, thus making the processes condensation is used in potentially much more efficient.

Design And Testing Of Experimental Langmuir Turbulence Facilities, Zongze Li

USF Tampa Graduate Theses and Dissertations

Langmuir Circulation is a common phenomenon driven by wind in oceans and lakes and was first studied by Langmuir in 1927. According to various ocean observations, this kind of phenomenon plays an important role in many phenomena such as the aggregation of bubbles, the distribution of plankton as well as the mixing of spilled oil and sediment in the ocean. To study this, an experimental facility has been developed in the lab which creates a small scale version of Langmuir Circulation.

This thesis is about the design and testing of this tank and surrounding aluminum frame, as well as the …

Turbine Passage Design Methodology To Minimize Entropy Production-A Two-Step Optimization Strategy, Paht Juangphanich, Cis De Maesschalck, Guillermo Paniagua

School of Aeronautics and Astronautics Faculty Publications

Rapid aerodynamic design and optimization is essential for the development of future turbomachinery. The objective of this work is to demonstrate a methodology from 1D mean-line-design to a full 3D aerodynamic optimization of the turbine stage using a parameterization strategy that requires few parameters. The methodology is tested by designing a highly loaded and efficient turbine for the Purdue Experimental Turbine Aerothermal Laboratory. This manuscript describes the entire design process including the 2D/3D parameterization strategy in detail. The objective of the design is to maximize the entropy definition of efficiency while simultaneously maximizing the stage loading. Optimal design trends are …

Happy Hours Are A Godsend, Krishna Pakala, Diana Bairaktarova, Samantha Schauer

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Office hours that happen in a virtual environment are called virtual office hours. This type of student-faculty interaction can be easily hosted from a faculty computer/mobile device/tablet. With an invitation, students can login to the online session and join their instructor and peers in a virtual space. Using mobile technologies, students can join virtual office hours from a variety of locations including a library, outdoors, on a commute ride home, while caring for children, eating dinner, and even while grocery shopping. Virtual office hours allow for more flexibility of student-faculty interaction. They are an alternative to traditional office hours. This …

Work In Progress: First-Year Engineering College Students: Value Created From Participating In A Living/Learning Community, Krishna Pakala, Kim M.B. Tucker, Samantha Schauer

Mechanical and Biomedical Engineering Faculty Publications and Presentations

This Work in Progress paper examines how to capture the perceived value obtained from firstyear engineering college students (FYECS) from participating in the Engineering and Innovation Residential College (EIRC), a living learning community (LLC). People are social by nature and thrive through collaborating and living with others who share similar passions; however, oftentimes FYECS do not have a community of like-minded peers where support, innovation, discourse, and collaboration can take place. Adding to FYECS struggles is the fact that many do not have a mentor in their related field and are unable to start building their professional repertoire, network, technical …

Zinc Ferrite Based Gas Sensors: A Review, Kaidi Wu, Jianzhi Li, Chao Zhang

Manufacturing & Industrial Engineering Faculty Publications

Flammable, explosive and toxic gases, such as hydrogen, hydrogen sulfide and volatile organic compounds vapor, are major threats to the ecological environment safety and human health. Among the available technologies, gas sensing is a vital component, and has been widely studied in literature for early detection and warning. As a metal oxide semiconductor, zinc ferrite (ZnFe2O4) represents a kind of promising gas sensing material with a spinel structure, which also shows a fine gas sensing performance to reducing gases. Due to its great potentials and widespread applications, this article is intended to provide a review on the latest development in …

Analysis Of The System Response Of A Spray Passive Downdraft Evaporative Cooling System, Daeho Kang, Richard K. Strand

Publications and Research

A spray Passive Downdraft Evaporative Cooling (PDEC) system achieves great savings for space cooling and improves indoor environmental quality by supplying a large amount of fresh outdoor air. As previous studies heavily focused on the energy saving capability of a spray PDEC system due to lack of methods for a detailed analysis, the influence of cool humid supply air from a spray PDEC system in a space in buildings has not been comprehensively studied. This study is intended to evaluate the competence of a spray PDEC system as a primary cooling system in typical spaces in a primary school building …

The Effect Of Hydro-Meteorology On Ship Collision Avoidance In Heavy Traffic Areas With A Simplified Simulation Model, Ming-Chung Fang, Kun-Yuan Tsai, Chih-Chung Fang

Journal of Marine Science and Technology–Taiwan

On the basis of the ship collision avoidance steering system in calm water developed by the authors, this paper upgrades the numerical simulation model by considering various hydrometeorological factors for ships with nonuniform movement. A real-time simulator was used for the numerical simulation of the container ship. To clarify the validity of the maneuvering mathematical model, sea trial results for the container ship were compared with the results for the present simulation system in terms of turn trajectory. In this study, a numerical technique based on Nomoto’s second-order model was employed to investigate the turning characteristics of a container ship. …

Crack Propagation And Microstructural Transformation On The Friction Surface Of A High-Speed Railway Brake Disc, Zhizhong Wang, Jianmin Han, Joseph P. Domblesky, Zhiqiang Li, Xinguang Fan, Xiaolong Liu

Mechanical Engineering Faculty Research and Publications

While brake disc wear represents a significant problem in high-speed rail systems, the progressive development of fatigue cracks during successive braking cycles also plays a great role in braking integrity. The modified microstructure consisting of a white etching layer (WEL) containing nanosized ferrite was observed on the friction surface of worn brake discs. In order to analyze how sequential thermal and mechanical stress affected crack propagation and microstructure evolution in brake discs, successive braking cycles were simulated on a full-scale braking bench test rig. Crack initiation and propagation mechanisms were proposed based on the experimental results, i.e., (i) occurrence of …

Identifying Nonlinear Oscillators By An Energetic Functional In The Linear Space Of Temporal Boundary Functions, Chein-Shan Liu, Yung-Wei Chen, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

We resolve the inverse problems of a second-order nonlinear oscillator to recover time-dependent damping function and nonlinear restoring force, with the help of temporal boundary data measured at initial time and final time. By using these data, a sequence of temporal boundary functions of time is derived, which satisfy the measured temporal boundary conditions automatically, and are at least the fourth-order polynomials of time. All the temporal boundary functions and zero element constitute a linear space, and a new concept of energetic functional is introduced in the linear space, of which the energy is preserved for each energetic temporal boundary …

Minimizing Induced Drag With Weight Distribution, Lift Distribution, Wingspan, And Wing-Structure Weight, Warren F. Phillips, Douglas F. Hunsaker, Jeffrey D. Taylor

Mechanical and Aerospace Engineering Student Publications and Presentations

Because the wing-structure weight required to support the critical wing section bending moments is a function of wingspan, net weight, weight distribution, and lift distribution, there exists an optimum wingspan and wing-structure weight are presented for rectangular wings with four different sets of design constraints. These design constraints are fixed lift distribution and net weight combined with 1) fixed maximum stress and wing loading, 2) fixed maximum deflection and wing loading, 3) fixed maximum stress and stall speed and 4) fixed maximum deflection and stall speed. For each of these analytic solutions, the optimum wing-structure weight is found to depend …

Implementation Of Visual Supplements To Strengthen Pedagogical Practices And Enhance The Physical Understanding Of Fundamental Concepts In Engineering Mechanics, Eleazar Marquez, Samuel Garcia, Samuel Molina

Mechanical Engineering Faculty Publications

Mechanical Engineering is a discipline highly dependent on designing and implementing mechanical, thermal, or energy systems for the improvement of the human environment. Thus being a proficient Engineer involves having a strong mathematical background and a thorough physical understanding on how systems operate in order to apply analytical or numerical schemes during a design process. However, most of the students’ academic development is centered on deriving tedious equations and solving textbook problems, which are difficult to visualize and physically understand, and cloud their intuitive nature to comprehend a problem on its entirety. These conventional approaches and methods of disseminating content …

A Method For Generating Random Vibration Using Acceleration Kurtosis And Velocity Kurtosis, Daichi Nakai, Katsuhiko Saito

Journal of Applied Packaging Research

Random vibration tests for packaging are conducted to confirm safety during shipping by truck. However, there is a difference between the traditional random vibration tests and the real vibrations on the truck bed. One reason for this difference is the shock caused by road roughness. Hence, many studies have been conducted to improve random vibration testing. In these studies, the root mean square, power spectral density, kurtosis, and probability density of acceleration are considered. In this study, we show that the kurtosis and probability density of velocity are also important factors for such tests and propose a new method for …

A Multi-Fidelity Prediction Of Aerodynamic And Sonic Boom Characteristics Of The Jaxa Wing Body, Forrest L. Carpenter, Paul G. A. Cizmas, Christian R. Bolander, Ted N. Giblette, Doug F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

This paper presents a detailed comparison between the linear panel solver PANAIR A502 and the in-house Navier–Stokes solver UNS3D for a supersonic low-boom geometry. The high-fidelity flow solver was used to predict both the inviscid and laminar flow about the aircraft geometry. The JAXA wing body was selected as the supersonic low-boom geometry for this study. A comparison of the undertrack near-field pressure signatures showed good agreement between the three levels of model fidelity along the first 0.8L of the signature. Large oscillations in the PANAIR results were observed. The PANAIR discrepancies were traced back to violations of the …

Characterizing Tilt Effects On Wind Plants, Ryan Scott

Dissertations and Theses

Tilting the nacelle of a wind turbine modifies entrainment into the wind plant and impacts total efficiency. Extreme angles can produce flying and crashing wakes where the wake either disrupts entertainment from the undisturbed flow above or is decimated on the ground. The effect of tilt angle on downstream wake behavior was investigated in a series of wind tunnel experiments. Scale model turbines with a hub height and diameter of 12 cm were arranged in a Cartesian array comprised of four rows of three turbines each. Nacelle tilt was varied in the third row from -15° to 15° in chosen …

Adjustable Medical Assistance Bed, Michelle Callson, Andrew Chen, Deborah Flores, Devin Meadows

Mechanical Engineering Senior Theses

The objective of this project is to design and manufacture a bed that provides increased safety and convenience to patients needing physical assistance and their caregivers, specifically catering to special needs patients. The bed is designed to have variable height between 0” and 30” from the bottom of the mattress to the ground, allowing the patient to get into bed with minimal physical assistance from the caregiver. The design process for this product was organized in three subsystems: lifting mechanism, escape prevention, and frame. The lifting mechanism is designed to accommodate the bed’s variable height, as well as support the …

Pedal 4 Purification, Cory Yamagata, Coleton Rodd, Jonathan Keyes, Matthew Lograsso

Mechanical Engineering Senior Theses

The lack of access to clean drinking water remains one of the largest issues still facing humanity. The Pedal 4 Purification is a product that addresses this need by utilizing pre-existing bicycle infrastructure and local freshwater sources to allow people to purify their own drinking water on a daily basis. Attachable to any standard bicycle, the Pedal 4 Purification product consists of pump, purification, cart and adjustable kickstand subsystems that allow the operator to pump, purify and transport 40L of potable water. Pedaling at the reasonable rate of 60 rpm will provide the optimal flow rate of 1.54L/min through the …

Power-Assist Wheelchair Attachment, Catherine Van Blommestein, Ryan Boyce, Rosemary Cole, Matthew Marks

Mechanical Engineering Senior Theses

This senior design project sought to combine the best characteristics of manual and power wheelchairs by creating a battery-powered attachment to propel a manual wheelchair. The primary customer needs were determined to be affordability, portability, and travel on uneven surfaces. After the initial prototype, using a hub motor proved unsuccessful, so a second design was developed that consisted of a gear reduction motor and drive wheel connected to the back of the wheelchair by a trailing arm that could be easily attached/detached from the frame. The prototype of the second design succeeded in meeting most of the project goals related …

Automatic Romaine Heart Harvester, Jonathan Borst, Chuck Culberson, Andrew Torrance

Mechanical Engineering Senior Theses

The Romaine Robotics Senior Design Team developed a romaine lettuce heart trimming system in partnership with a Salinas farm to address a growing labor shortage in the agricultural industry that is resulting in crops rotting in the field before they could be harvested. An automated trimmer can alleviate the most time consuming step in the cut-trim-bag harvesting process, increasing the yields of robotic cutters or the speed of existing laborer teams. Leveraging the Partner Farm’s existing trimmer architecture, which consists of a laborer loading lettuce into sprungloaded grippers that are rotated through vision and cutting systems by an indexer, the …

Environment Chamber For Shape-Memory Alloy Testing, Luis Acevedo, Joseph Bodo, Nicholas Fernandes

Mechanical Engineering Senior Theses

The purpose of this project is to design, test, and build a temperature-controlled environment chamber to enable tensile testing of shape memory alloy (SMA) wire specimens at a temperatures ranging from 80-200°C. The most important design specifications were a maximum exterior wall temperature of 40°C and a maximum temperature variation along the specimen length of ±5°C, with end users' ease- of-use considered. Hand calculations and iterative finite element analysis (FEA) simulations in SolidWorks were used to verify design choices before proceeding with sourcing parts and materials, and assembly. Real-world implementation of the system showed a heat-up time of roughly 25 …

Micro-Ct Evaluation Of Defects In Ti-6al-4v Parts Fabricated By Metal Additive Manufacturing, Haijun Gong, Venkata Karthik Nadimpalli, Khalid Rafi, Thomas Starr, Brent Stucker

Manufacturing Engineering: Faculty Publications (2015-2023)

In this study, micro-computed tomography (CT) is utilized to detect defects of Ti-6Al-4V specimens fabricated by selective laser melting (SLM) and electron beam melting (EBM), which are two popular metal additive manufacturing methods. SLM and EBM specimens were fabricated with random defects at a specific porosity. The capability of micro-CT to evaluate inclusion defects in the SLM and EBM specimens is discussed. The porosity of EBM specimens was analyzed through image processing of CT single slices. An empirical method is also proposed to estimate the porosity of reconstructed models of the CT scan.

Design Of An Urban Garden Aquaponics System, Riley Albright-Borden, James Wang, Sydney Thompson

Interdisciplinary Design Senior Theses

The project objective is to create a durable, off-the-grid, large-scale aquaponics system consisting of over 90 sq. ft of growing space, a 650-gallon fishpond, and four types of sensors to transmit water quality data to the internet for remote water quality monitoring. The end goal of the project is to supplement produce grown in the garden to further increase fresh, nutritional options available in meals cooked and distributed by Loaves and Fishes Family Kitchen to combat food insecurity in San Jose. This report presents the need for a system, details the various subsystems, and the rationale for the designs. It …

Silica-Coated Metallic Nanoparticle-Based Hierarchical Super-Hydrophobic Surfaces Fabricated By Spin-Coating And Inverse Nanotransfer Printing, Shengjie Zhai, Hui Zhao

Mechanical Engineering Faculty Research

By combining spin coating and inverse nanotransfer printing, silica-coated gold nanoparticles are patterned onto polydimethylsiloxane (PDMS) superhydrophobic surfaces to form a hierarchical structure. A layer of nanoparticles is spin-coated on a flat silicon substrate serving as the stamp, which is then transferred to the raised regions of PDMS surfaces. Our inverse nanotransfer printing is in contrast to the standard nanotransfer printing, which transfers metal from the raised regions of a stamp to a flat PDMS surface. The fabricated hierarchical surface exhibits a higher contact angle and delays the Cassie-Wenzel transition during evaporation of a sessile droplet, indicating an improvement of …

Non-Einstein Viscosity Phenomenon Of Acrylonitrile–Butadiene–Styrene Composites Containing Lignin–Polycaprolactone Particulates Highly Dispersed By High-Shear Stress, Sing-Hoon Kim, Kisuk Choi, Kyouk Ryeol Choi, Taesung Kim, Jonghwan Suhr, Kwang Jin Kim, Hyoung Jin Choi, Jae-Do Nam

Mechanical Engineering Faculty Research

Lignin powder was modified via ring-opening polymerization of caprolactone to form a lignin–polycaprolactone (LPCL) particulate. The LPCL particulates were mixed with an acrylonitrile–butadiene–styrene (ABS) matrix at an extremely high rotational speed of up to 3000 rpm, which was achieved by a closed-loop screw mixer and in-line melt extruder. Using this high-shear extruding mixer, the LPCL particulate size was controlled in the range of 3395 nm (conventional twin-screw extrusion) down to 638 nm (high-shear mixer of 3000 rpm) by altering the mixing speed and time. The resulting LPCL/ABS composites clearly showed non-Einstein viscosity phenomena, exhibiting reduced viscosity (2130 Pa·s) compared to …

Infinite Photovoltaic Solar Arrays: Considering Flux Of Momentum And Heat Transfer, Andrew D. S. Glick

Dissertations and Theses

Large scale solar farms supply an increasing amount of the worlds electricity supply. However, in order to reach cost parity with fossil fuels, further reductions are necessary. Towards this end, photovoltaic (PV) panel cooling becomes increasingly important; high temperatures both decrease efficiency and panel lifetime. To better understand, characterize, and exploit the natural convective cooling of utility scale solar farms, a model solar farm was created. Using both thermal measurements and particle image velocimetry to characterize heat transfer and velocity fields, wind tunnel experiments were conducted using the model solar farm. Three parameters were examined for their effect on heat …

Biomethane Production From Distillery Wastewater, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Distillery wastewater treatment is a great ecological problem, for example, India produces 2.7 billion liters of alcohol that results in 40 billion liters of wastewater. However, this material can be seen as a resource since 11 million cubic meters of biogas at 60% methane could be produced in addition to cleaning the water. The distillery has two options of what to do with the biogas. The first is to use the biogas to fuel the distillery making the production plant more energy efficient and removing some of the need to buy natural gas. The other is to upgrade the biogas …