Mechanical Engineering Commons^™

Experimental And Numerical Investigation Of The Mechanism Of Blast Wave Transmission Through A Surrogate Head, Yi Hua, Praveen Akula, Linxia Gu, Jeff Berg, Carl A. Nelson

Mechanical & Materials Engineering Faculty Publications

This work is to develop an experiment-validated numerical model to elucidate the wave transmission mechanisms through a surrogate head under blast loading. Repeated shock tube tests were conducted on a surrogate head, i.e., water-filled polycarbonate shell. Surface strain on the skull simulant and pressure inside the brain simulant were recorded at multiple locations. A numerical model was developed to capture the shock wave propagation within the shock tube and the fluid-structure interaction between the shock wave and the surrogate head. The obtained numerical results were compared with the experimental measurements. The experiment-validated numerical model was then used to further ...

Building Fuel-Efficient Vehicles Is Goal Of Cedarville Engineers, Josiah Clemons

News Releases

Racing in supermileage car competitions has been the norm at Cedarville Univesity since 1991. In these competitions, first with SAE (1991-2010) and now with Shell (since 2007), the teams of Cedarville engineering students have gained practical learning knowledge while winning awards in the process.

Students At The University Of Tennessee Utilize Ethanol For Advanced Vehicle Technology Competition, Karson Nichole Stone

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

The Exhibition of Undergraduate Research and Creative Achievement (EURēCA) is an annual event that showcases research and creative activities by currently enrolled undergraduate students in collaboration with a University of Tennessee, Knoxville faculty mentor. Entries can be individual or group projects and are judged by a panel of UT faculty members. The UT Knoxville Office of Research & Engagement coordinates this unique competition to encourage, support, and reward undergraduate participation in the campus research enterprise. An added value is the development of faculty mentoring relationships.

Design Of Surgical End Effectors For Robotic Parallel Continuum Manipulators, Andrew L. Orekhov, Caroline E. Bryson, D. Caleb Rucker

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Exhibition of Undergraduate Research and Creative Achievement

Six Degree-Of-Freedom, Musculotendon Joint Stiffness: Examples With The Knee, Joshua G. A. Cashaback

Open Access Dissertations and Theses

Increased muscle stiffness helps prevent excessive movement that can lead to ligament and soft-tissue damage. There is empirical evidence suggesting that muscles are important in preventing injuries caused by excessive translational movements. Very little is known, however, on how our muscles provide translational stiffness. This thesis uses complementary theoretical (Chapters 2 and 3) and experimental (Chapter 4) techniques to address how muscles provide translational joint stiffness.

In Chapters 2 and 3, we used an elastic energy approach to successfully derive equations that quantify muscular contributions to joint stiffness. From the equations, we were able to determine how the geometric orientation ...

Synthetic Jet Micropump, Sherif Abdou

Open Access Dissertations and Theses

The production of a novel micropump based on the synthetic jet principle is investigated both numerically and experimentally. The proposed micropump consists of a synthetic jet actuator driven by a vibrating diaphragm issuing into an inverted T- shaped channel structure forming the inlet/outlet channels of the pump.

The software package Ansys is used to perform numerical investigations of the operation of the proposed micropump. Simulations were performed to study the effect of changing the inlet/outlet channel dimensions as well as the operating frequency, amplitude and duty cycle of the excitation signal. Inlet/outlet channel widths ranging from 200 ...

Synthetic Jet Actuator For Active Flow Control, Sherif Abdou

Open Access Dissertations and Theses

This thesis investigates the characteristics of a long aspect ratio synthetic jet actuator and its application for the active control of the vibrations of the downstream cylinder in a tandem cylinder arrangement.

A long aspect ratio synthetic jet is produced through an axial slit along part of the length of a cylinder. The jet is excited acoustically by a pair of loudspeakers mounted at the cylinder terminations. The study compares between the performance of two different slits with aspect ratios of 273 and 773. The comparison is based on the spanwise distribution of the mean jet velocity and phase between ...

Simulating Scwr Thermal-Hydraulics With The Modified Cobra-Tf Subchannel Code, Dinusha Wikumpiya Lokuliyana

Open Access Dissertations and Theses

Among the six GEN-IV reactor concepts recommended by the Gen-IV International Forum, supercritical water-cooled reactors (SCWR) have gained significant interests due to its economic advantage, technology and experience continuity. In the last few years, extensive R&D activities have been launched covering the various aspects of SCWR development, especially in thermal-hydraulic analysis. In Canada, most R&D projects are led by AECL or NRCan.

SCWR design and development require the modification of simulation codes used for design and safety demonstration of subcritical water-cooled reactors. This study modifies the subchannel code COBRA-TF, applicable to only subcritical water-cooled reactors, to a new ...

Flow Accelerated Corrosion In Single And Dual S-Shape Bends Under Single And Two Phase Annular Flow Conditions, Hazem Mohamed Mohamed Ahmed Mazhar

Open Access Dissertations and Theses

Flow Accelerated Corrosion (FAC) is defined as a flow enhanced mass transfer phenomenon that results in pipe wall thinning of the piping system and results in abrupt failure in some cases. FAC is controlled by the transport of corrosion species from the wall to the bulk fluid and is determined by the local distribution of the mass transfer coefficient. The overall objective of this research is to investigate the mass transfer in pipe bends arranged in single and dual S- shape configurations under single and annular two phase flow conditions. A novel wall dissolving mass transfer technique was developed to ...

Free Vibrations Of Interspersed Railway Track Systems In Three-Dimensional Space, Sakdirat Kaewunruen, Alex M. Remennikov, Akira Aikawa, Hirotaka Sakai

Sakdirat Kaewunruen

Statistically, the actual loading conditions for railway tracks are rather dynamic and transient. The dynamic loadings due to train and track interactions redistribute from the rails to the rail pad, from the rail pad to the railway sleeper, and from the railway sleeper to the underlying ground. Commonly, railway sleeper in track systems is modeled as a beam on elastic foundation. This study makes use of a calibrated finite element model of railway sleepers in a track system, in order to investigate the resonant frequencies and associated mode shapes of railway components in interspersed track systems. The numerical model takes ...

Nano-Multilayered Self-Adaptive Hard Pvd Coatings For Dry High Performance Machining, Li Ning

Open Access Dissertations and Theses

In this research~ quaternary nitride nano-multilayered coatings of the form TiAICrN/MexN were comprehensively characterized. Based on this research principles which can be applied for guiding coating design were developed using the concept of self-adaptability.

Comprehensive studies were performed on the following aspects: the tlibological properties of the coatings at elevated temperatures, tool life, and cutting forces, tribo-oxide formation, wear mechanisms and wear progression, chip characteristics and the mechanisms of chip formation. The techniques applied for comprehensive characterization of the coatings were mainly Scanning Electron MicroscopelEnergy Dispersive Spectrometer (SEMIEDS) and X-ray Photoelectron Spectroscopy (XPS).

The concept of self-adaptability as applied ...

Characterizing Phantom Arteries With Multi-Channel Laser Ultrasonics And Photo-Acoustics, Jami L. Johnson, Kasper Van Wijk, Michelle Sabick

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Multi-channel photo-acoustic and laser ultrasonic waves are used to sense the characteristics of proxies for healthy and diseased vessels. The acquisition system is non-contacting and non-invasive with a pulsed laser source and a laser vibrometer detector. As the wave signatures of our targets are typically low in amplitude, we exploit multi-channel acquisition and processing techniques. These are commonly used in seismology to improve the signal-to-noise ratio of data. We identify vessel proxies with a diameter on the order of 1 mm, at a depth of 18 mm. Variations in scattered and photo-acoustic signatures are related to differences in vessel wall ...

Monitoring In-Service Performance Of Fibre-Reinforced Foamed Urethane Sleepers/Bearers In Railway Urban Turnout Systems, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Special track systems used to divert a train to other directions or other tracks are generally called \'railway turnout\'. A traditional turnout system consists of steel rails, switches, crossings, steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints and construction ...

Wooden Bikes Present Capstone Challenge For Engineering Students, Jenni Hodges

News Releases

Four Cedarville seniors are building and testing wooden bicycles for a capstone engineering project. Team leader Jake Miller said the project offers a unique opportunity for students to connect their interests in engineering, woodworking and cycling.

High-Resolution, Real-Time Three-Dimensional Shape Measurement On Graphics Processing Unit, Nikolaus L. Karpinsky, Morgan D. Hoke, Vincent Chen, Song Zhang

Mechanical Engineering Publications and Papers

A three-dimensional (3-D) shape measurement system that can simultaneously achieve 3-D shape acquisition, reconstruction, and display at 30 frames per second (fps) with 480,000 measurement points per frame is presented. The entire processing pipeline was realized on a graphics processing unit (GPU) without the need of substantial central processing unit (CPU) power, making it achievable on a portable device, namely a laptop computer. Furthermore, the system is extremely inexpensive compared with similar state-of-art systems, making it possible to be accessed by the general public. Specifically, advanced GPU techniques such as multipass rendering and offscreen rendering were used in conjunction ...

The Penn Haptic Texture Toolkit For Modeling, Rendering, And Evaluating Haptic Virtual Textures, Heather Culbertson, Juan Jose Lopez Delgado, Katherine J. Kuchenbecker

Departmental Papers (MEAM)

The Penn Haptic Texture Toolkit (HaTT) is a collection of 100 haptic texture and friction models, the recorded data from which the models were made, images of the textures, and the code and methods necessary to render these textures using an impedance-type haptic device such as a SensAble Phantom Omni. This toolkit was developed to provide haptics researchers with a method by which to compare and validate their texture modeling and rendering methods. The included rendering code has the additional benefit of allowing others, both researchers and designers, to incorporate our textures into their virtual environments, which will lead to ...

Hvac Chapter 1, Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.

Non-Oxidative And Oxidative Torrefaction Characterization And, Wei-Hsin Chen

Wei-Hsin Chen

No abstract provided.

Using “Expert Employees” To Identify Duties And Tasks For Cadd Technicians In North Central Idaho: Lessons Learned From A Modified Dacum Process, Raymond A. Dixon Ph.D., Linda S. Stricklin Ph.D.

Online Journal for Workforce Education and Development

Objective: We conducted a job analysis to identify the competency profile of an entry level CADD technician in North central Idaho. Background: In 2011, the Clearwater Economic Development Association and NIMA collaborated with Lewis-Clark State College and the University of Idaho in a project to strengthen the capacity of Career and Technology Education (CTE) teachers to teach computer aided drafting and designing (CADD). An application to the National Science Foundation, Advanced Technology Education (NSF ATE) program was made and funding began July of 2011. Method: A modified DACUM was used. A total of seven expert workers from six companies ...

Absolute Three-Dimensional Shape Measurement Using Coded Fringe Patterns Without Phase Unwrapping Or Projector Calibration, William F. Lohry, Vincent Chen, Song Zhang

Mechanical Engineering Publications and Papers

This paper presents a novel stereo-phase-based absolute three-dimensional (3D) shape measurement that requires neither phase unwrapping nor projector calibration. This proposed method can be divided into two steps: (1) obtain a coarse disparity map from the quality map; and (2) refine the disparity map using wrapped phase. Fringe patterns are modified to encode the quality map for efficient and accurate stereo matching. Experiments demonstrated that the proposed method could achieve high-quality 3D measurement even with extremely low-quality fringe patterns.