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Assessment Of Various Parametric Effects On The Performance Of A Commercial Grade Photovoltaic Solar Panel, Susanta K. Das, David Frank

Mechanical Engineering Publications

This paper presents the implementation of an integrated photovoltaic solar panel model which includes all the necessary parameters in order to simulate and analyze using Matlab/Simulink software. The integrated photovoltaic model is validated with Matlab/Simulink simulation for a commercially available 100W photovoltaic solar panel module. Using the commercial solar panel specifications, such as solar irradiation, panel temperature, etc. the integrated model solved with Matlab/Simulink returns an I-V and PV performance characteristics under various conditions which enabled detailed analysis, assessment of parametric effect on the performance of the solar panel. According to the model simulation results for a commercial RNG-100D solar …

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 …

Vibration Analysis Of Healthy Skin: Toward A Noninvasive Skin Diagnosis Methodology, Rakshita Panchal, Luke Horton, Peyman Poozesh, Javad Baqersad, Mohammadreza Nasiriavanaki

Mechanical Engineering Publications

Several noninvasive imaging techniques have been developed to monitor the health of skin and enhance the diagnosis of skin diseases. Among them, skin elastography is a popular technique used to measure the elasticity of the skin. A change in the elasticity of the skin can influence its natural frequencies and mode shapes. We propose a technique to use the resonant frequencies and mode shapes of the skin to monitor its health. Our study demonstrates how the resonant frequencies and mode shapes of skin can be obtained using numerical and experimental analysis. In our study, natural frequencies and mode shapes are …

Characterization Of Solid Oxide Fuel Cells With Lscf-Sdc Composite Cathodes, Gianfranco Digiuseppe, Venkatesh Boddapati

Mechanical Engineering Publications

This paper reports the study of an anode-supported SOFC cell containing an LSCF-SDC composite cathode. The SOFC cell was tested at different temperatures and reactant flow rates. After testing, the cell was sectioned and characterized using SEM/EDS. Such analysis indicated that no structural damage and no significant interdiffusion of elements among the layers occurred. The measured electrochemical performance data at different temperatures indicate an Arrhenius behavior or temperature activated processes. The low-porosity anode functional layer appears to be very sensitive to low hydrogen contents. The electrochemical performance is also affected by changing air flow rates.

A Novel Approach To Visualize And Quantify The Transient Air Infiltration/Exfiltration In Walk-In Coolers, Ramin Faramarzi, Homayun K. Navaz, K. Kamensky

Mechanical Engineering Publications

Walk-in coolers are room-sized, insulated, and refrigerated compartments for food product storage. Walk-ins have areas equal or below 280 m2 (3,000 ft2), and are classified either as coolers operating above 0 degrees C (32 degrees F) (medium-temperature) to store fresh fruit, vegetables, and dairy products, or freezers that operate below 0 degrees C (32 degrees F) (low-temperature) to meet health and safety standards of frozen food products. Walk-ins are typically found in restaurants as well as small- and medium-to-large grocery stores or supermarkets.

Xps Studies Of Lscf Interfaces Afer Cell Testing, Gianfranco Digiuseppe, Venkatesh Boddapati, Hiten Mothikhana

Mechanical Engineering Publications

The motivation of this investigation is to explore the possibility of using the depth profile capability of XPS to study interfaces after SOFC button cell testing. The literature uses XPS to study various cathode materials but has devoted little to the understanding of various cathode interfaces especially after testing. In this work, an SOFC button cell is first tested, and then, the LSCF cathode, barrier layer, and electrolyte are sputtered away to study the behavior of different interfaces. This work has shown that some elements have moved into other layers of the SOFC cell. It is argued that the migration …

Long-Term Cell Testing Of Interlayer-Free Lanthanum Strontium Cobalt Ferrite Cathodes For Solid Oxide Fuel Cells, Gianfranco Digiuseppe, Venkatesh Boddapati, Hiten Mothikhana

Mechanical Engineering Publications

Sub-stoichiometric LSCF nanopowders with composition of (La0.6Sr0.40)0.95Co0.2Fe0.80O3-d were prepared using a nitrate-glycine process. The particle size is estimated to be 28.8 nm using the Scherrer equation. A sintering study and pull test was done to determine the quality of LSCF adhesion to the YSZ electrolyte. It was found that firing the cathode at 850oC does not provide the best adhesion, but button cell testing data indicate that the performance is stable over relatively long-term tests. The cell performance is not up to par to state-of-the-art Ni-YSZ/YSZ/SDC/LSCF where a barrier layer is used and the cathode is fired at high temperatures. …

Drivers Of Research Topic Selection For Engineering Doctoral Students, Erika A. Mosyjowski, Shanna R. Daly, Diane L. Peters

Mechanical Engineering Publications

In this study, we explored engineering doctoral students’ motivations for selecting their research topic. The extent to whichindividuals are intrinsically or extrinsically motivated and the autonomy they have to make their own decisions hasimplications for their enjoyment of and success at a particular task. Given the importance of motivation, we sought toaddress a gap in the understanding of how doctoral students in engineering decide on a particular problem to study. Ourfindings are based on interviews with students with varying past educational and professional experiences that enable us tocapture a wide range of motivations for engineering PhD students’ research subject decisions. …

Injury Severity Data For Front And Second Row Passengers In Frontal Crashes, Theresa Atkinson, Leszek Gawarecki, Massoud Tavakoli

Mechanical Engineering Publications

The data contained here were obtained from the National Highway Transportation Safety Administration׳s National Automotive Sampling System – Crashworthiness Data System (NASS-CDS) for the years 2008–2014. This publically available data set monitors motor vehicle crashes in the United States, using a stratified random sample frame, resulting in information on approximately 5000 crashes each year that can be utilized to create national estimates for crashes. The NASS-CDS data sets document vehicle, crash, and occupant factors. These data can be utilized to examine public health, law enforcement, roadway planning, and vehicle design issues. The data provided in this brief are a subset …

A General-Purpose Multiphase/Multispecies Model To Predict The Spread, Percutaneous Hazard, And Contact Dynamics For Nonporous And Porous Substrates And Membranes, Homayun K. Navaz, Ali R. Zand, Amir Gat, Theresa S. Atkinson

Mechanical Engineering Publications

A computational model to solve the coupled transport equations with chemical reaction and phase change for a liquid sessile droplet or the contact and spread of a sessile droplet between two approaching porous or non-porous surfaces, is developed. The model is general therefore it can be applied to toxic chemicals (contact hazard), drug delivery through porous organs and membranes, combustion processes within porous material, and liquid movements in the ground. The equation of motion and the spread of the incompressible liquid available on the primary surface for transfer into the contacting surface while reacting with other chemicals (or water) and/or …

Biomechanical Performance Of Variable And Fixed Angle Locked Volar Plates For The Dorsally Comminuted Distal Radius, Patrick Atkinson, D. Martineau, J. Shorez, C. Beran, A. G. Dass

Mechanical Engineering Publications

Background

The ideal treatment strategy for the dorsally comminuted distal radius fracture continues to evolve. Newer plate designs allow for variable axis screw placement while maintaining the advantages of locked technology. The purpose of this study is to compare the biomechanical properties of one variable axis plate with two traditional locked constructs.

Methods

Simulated fractures were created via a distal 1 cm dorsal wedge osteotomy in radius bone analogs. The analogs were of low stiffness and rigidity to create a worst-case strength condition for the subject radius plates. This fracture-gap model was fixated using one of three different locked volar …

Design, Modeling And Development Of A Serial Hybrid Motorcycle With Hcci Engine, Yuh-Yih Wu, Chen Duan, Kai-Xian Hong, Hsien-Chi Tsai, Craig Hoff

Mechanical Engineering Publications

This paper discusses the design, modeling, and development of small motorcycle equipped with a HCCI engine in an series hybrid configuration. A mathematical model was developed using MATLAB/Simulink and used to size the powertrain components and to predict fuel economy. A conventional 125 cc spark ignition engine was modified to run in HCCI combustion mode and integrated into a prototype vehicle. Dual-fuel and external EGR strategies were used to upgrade the engine speed and torque capabilities of the engine to meet the requirements of the powertrain. An electrical generator, hub-motor, battery pack and other power electronics devices were used to …

Dynamics And Stability Of Two-Potential Flows In The Porous Media, Bojan Markicevic, Branko Bijeljic, Homayun K. Navaz

Mechanical Engineering Publications

The experimental and numerical results of the capillary-force-driven climb of wetting liquid in porous media, which is opposed by the gravity force, are analyzed with respect to the emergence of a multiphase flow front and flow stability of the climbing liquid. Two dynamic characteristics are used: (i) the multiphase flow front thickness as a function of time, and (ii) the capillary number as a function of Bond number, where both numbers are calculated from the harmonic average of pores radii. Throughout the climb, the influence of capillary, gravity, and viscous force variations on the flow behavior is investigated for different …

On The Effect Of Functionally Graded Materials On Resonances Of Rotating Beams, Arnaldo J. Mazzei Jr.

Mechanical Engineering Publications

Radially rotating beams attached to a rigid stem occur in several important engineering applications. Some examples include helicopter blades, turbine blades and certain aerospace applications. In most studies the beams have been treated as homogeneous. Here, with a goal of system improvement, non-homogeneous beams made of functionally graded materials are explored. The effects on the natural frequencies of the system are investigated. Euler-Bernoulli theory, including an axial stiffening effect and variations of both Young's modulus and density, is employed. An assumed mode approach is utilized, with the modes taken to be beam characteristic orthogonal polynomials. Results are obtained via Rayleigh-Ritz …

Capillary Climb Dynamics In The Limits Of Prevailing Capillary And Gravity Force, B. Bijeljic, B. Markicevic, Homayun K. Navaz

Mechanical Engineering Publications

The dynamics of capillary climb of a wetting liquid into a porous medium that is opposed by gravity force is studied numerically. We use the capillary network model, in which an actual porous medium is represented as a network of pores and throats, each following a predefined size distribution function. The liquid potential in the pores along the liquid interface within the network is calculated as a result of capillary and gravity forces. The solution is general, and accounts for changes in the climbing height and climbing velocity. The numerical results for the capillary climb reveal that there are at …

Evaluating Impact Attenuator Performance For A Formula Sae Vehicle, Jason Fahland, Craig Hoff, Janet Brelin-Fornari

Mechanical Engineering Publications

Formula SAE® is one of several student design competitions organized by SAE International. In the Formula SAE events undergraduate and graduate students are required to conceive, design, fabricate and compete with a small, formula-style, race car. Formula SAE safety rules dictate a 7 m/s (or approximately 15.65 mph) frontal crash test for nose mounted impact attenuators. These rules are outlined in section B3.21 of the Formula SAE rule book. Development and testing methods of these energy absorbing devices have varied widely among teams. This paper uses real world crash sled results to research methods for predicting the performance of aluminum …

Impact Assessment Of Problem-Based Learning In An Engineering Science Course, Karim J. Nasr, Bassem Ramadan

Mechanical Engineering Publications

This paper presents the development and implementation of Problem-Based Learning (PBL) in an engineering thermodynamics course at Kettering University. In this project, the thermodynamics course was restructured as modules presenting practical applications first, whereas principles were introduced just-in-time and as encountered. Theoretical information was presented to support the understanding of knowledge as students applied inquiry-based learning. These modules were carefully designed to reflect traditional concepts but made more exciting as students discover the need for the laws and principles. The classroom format was interactive, cooperative and revolves around students' needs. Formative and summative assessment tools were designed to examine the …

Air Curtains Of Open Refrigerated Display Cases Revisited: A New Technique For Infiltration Rate Measurements, M. Amin, Homayun K. Navaz, D. Dabiri, Ramin T. Faramarzi

Mechanical Engineering Publications

Air curtains are created in open refrigerated vertical display cases for creating an invisible barrier between the cold air inside and the warm air outside the case. A systematic approach is developed to minimize the entrainment and infiltration of warm air into the case by optimizing the performance of an air curtain through adjusting pertinent flow parameters and case geometry. A modular display case was manufactured for the parametric studies. In this modular display case the geometry and flow parameters were changed and the infiltration rate was measured using a new technique, tracer gas method, which could be performed noticeably …

A Simple Laboratory Experiment For The Measurement Of Single Phase Permeability, Ali R. Zand, Yuri Sikorski, Matthew S. Sanders, Homayun K. Navaz

Mechanical Engineering Publications

A simple experiment for measuring single-phase permeability of fully saturated porous medium is introduced. The experiment utilizes radial flow of a non-volatile wetting fluid through a porous medium such as ceramic tile, concrete or sand. The radial position of flow front is measured as a function of time and the collected data are analyzed using Darcy's Law to determine the permeability. In addition, the phenomenon of the multiphase flow through the medium with a broad pore size distribution is demonstrated.