bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developing an Effective Platform for Introducing Mechanical Engineering in a Large Public University
Authors: Lilly Blaine W. , Abrams Lisa M. , Neal Michael , Srinivasan K. , Mendelsohn Daniel 
Published: October 2013

In conjunction with a shift from an academic calendar based on ten–week quarters to one based on semesters, the Department of Mechanical and Aerospace Engineering at The Ohio State University has completely re–designed the mechanical engineering curriculum. As a part of this re–design, the MAE department has added a new course for sophomores entering the department that will emphasize hands–on skills in machining and electronics while simultaneously giving students a broad introduction to the kinds of problems that mechanical engineers typically confront in industrial practice.
This paper describes the evolution of our thinking as we created the teaching platform that is the heart of the course, a multi–cylinder compressed air motor. Lectures are structured to provide ‘just in time’ information to the students as they build and test this platform in the laboratory. It was crucial to create a device that would be complex enough to challenge the students and provide an opportunity to explore the widest possible range of mechanical engineering concepts. After a review of similar courses in other programs, we decided to employ a multi–cylinder compressed air motor, controlled by a commercially available microprocessor, as the teaching platform.
Because the course will be required of all students entering the major, an overriding constraint on the design is that the device is simple enough for three hundred students a year, working in teams, to construct and test it. At the same time, the air motors must also be complex enough to support the learning objectives of this course and subsequent courses in the curriculum. Our final design is a direct–injection six–cylinder radial compressed air motor that is controlled by an Arduino© microprocessor. Students will spend five weeks machining and assembling the motors in the machine shop, another four weeks learning to program the Arduino© to control the motor, and the remainder of the term testing and analyzing the performance of the motors.
The air motors allow us to introduce students to machine design, engine design, thermodynamics, fluid flow, vibrations, electronics, and controls. We have pilot tested this course twice, and find that the students quickly take ownership of the motors, and are quite interested in optimizing the design to improve performance.
Effect of Radiation Models on Coal Gasification Simulation
Authors: Lu Xijia , Wang Ting 
Published: October 2013

Adequate modeling of radiation heat transfer is important in CFD simulation of coal gasification process. In an entrained-flow gasifer, the non-participating effect of coal particles, soot, ashes, and reactive gases could significantly affect the temperature distribution in the gasifier and hence affects the local reaction rate and life expectancy of wall materials. For slagging type gasifiers, radiation further affects the forming process of corrosive slag on the wall which can expedite degradation of the refractory lining in the gasifier. For these reasons, this paper focuses on investigating applications of five different radiation models to coal gasification process, including Discrete Transfer Radiation Model (DTRM), P-1 Radiation Model, Rosseland Radiation Model, Surface-to-Surface (S2S) Radiation Model, and Discrete Ordinates (DO) Radiation Model. The objective is to identify the pros and cons of each model’s applicability to the gasification process and determine which radiation model is most appropriate for simulating the process in entrained-flow gasifiers.
The Eulerian-Lagrangian approach is applied to solve the Navier-Stokes equations, nine species transport equations, and seven global reactions consisting of three heterogeneous reactions and four homogeneous reactions. The coal particles are tracked with the Lagrangian method. Six cases are studied—one without the radiation model and the other five with different radiation models. The result reveals that the various radiation models yield uncomfortably large uncertainties in predicting syngas composition, syngas temperature, and wall temperature. The Rosseland model does not yield reasonable and realistic results for gasification process. The DTRM model predicts very high syngas and wall temperatures in the dry coal feed case. In the one-stage coal slurry case, DTRM result is close to the S2S result. The P1 method seems to behave stably and is robust in predicting the syngas temperature and composition; it yields the result most close to the mean, but it seems to underpredict the gasifier’s inner wall temperature.
Transport and Deposition of Ellipsoidal Fibers in Subject-Specific Lung Airways
Authors: Feng Yu , Kleinstreuer Clement 
Published: October 2013

Fine to ultrafine materials, such as spherical particles and fibers with their diverse applications ranging from cosmetics, cleaners and composites to nanomedicine are increasingly ubiquitous in the air we breathe. For example, the unique lung deposition patterns of nanoparticles and their ease-of-migration into the blood stream may cause severe health problems, as discussed by Oberdoerster et al. (2005). In contrast, multifunctional nanoparticles as well as micron fibers are also being used as drug carriers for cancer treatment (Zhang et al., 2011). While the transport and deposition of spherical nanoparticles has been analyzed (Kleinstreuer and Zhang, 2010; among others), the fate of ellipsoidal particles in subject-specific lung airways has hardly been addressed.
In this study, the Euler-Lagrange fluid-particle modeling approach (i.e., the Discrete Phase Method solver) has been employed in Fluent 13.0 (ANSYS, Canonsburg, PA). User-supplied C-programs have been added to simulate ellipsoidal fibers transport and orientation effects. The computer simulation model has been validated for fiber transport and deposition in a circular tube (Tian et al., 2012). Additionally, transitional airflow patterns were analyzed and local deposition efficiencies compared for spherical particles and fibers in a realistic human respiratory system. The capability of ellipsoidal fibers migrating into deeper lung regions was indicated and fiber deposition “hot spots” were discussed. The numerical results expand the basic understanding of the dynamics of non-spherical particles in realistic shear flows, and can be used to investigate the fate of inhaled toxic or therapeutic materials.
Influence of Plaque Stiffness on Change of Blood Vessel Geometry Leading Hemodynamical Changes in PVA-H Stenosis Models
Authors: Shimizu Yasutomo , Shida Shuya , Funamoto Kenichi , Hayase Toshiyuki , Ohta Makoto 
Published: October 2013

One of the main factors affecting blood flow conditions in stenotic arteries is plaque geometry. Plaques can be deformed by the internal pressure, and hence plaque behavior varies depending on its stiffness. Blood flow pattern around a plaque is complicated by plaque behavior, and these complications may lead to growth of the plaque itself. Thus, we can say that geometry and mechanical properties of a plaque, and blood flow will affect each other.
To understand the relationship between plaque stiffness and flow pattern, flow measurement using elastic models, which mimic the mechanical properties of blood vessels, is required. Flow patterns with steady flows and a range of hydrostatic pressures were observed by particle image velocimetry. The results show that the model is deformed by hydrostatic pressures. Furthermore, flow patterns are also changed as the results of model deformation, especially at reattachment points. Simultaneously, we performed a numerical simulation for finding a critical parameter of the flow patterns. These results show that the reattachment length increases in the model with high stenosis severity and in a vertically oriented parent artery. In conclusion, a parent artery and plaque can deform because of internal pressure, and these deformation will affect blood flow patterns.
Running the World on Renewables: Alternatives for Transmission and Low-Cost Firming Storage of Stranded Renewables as Hydrogen and Ammonia Fuels via Underground Pipelines
Authors: Leighty William C. , Holbrook John H. 
Published: October 2013

We must soon “run the world on renewables” but cannot, and should not try to, accomplish this entirely with electricity transmission. We need to supply all energy, not just electricity, from diverse renewable energy (RE) resources, both distributed and centralized, where the world’s richest RE resources — of large geographic extent and high intensity — are stranded: far from end-users with inadequate or nonexistent gathering and transmission systems to deliver the energy. Electricity energy storage cannot affordably firm large, intermittent renewables at annual scale, while carbon-free gaseous hydrogen (GH2) and liquid anhydrous ammonia (NH3) fuels can: GH2 in large solution-mined salt caverns, NH3 in surface tanks, both pressurized and refrigerated.
“Smart Grid” is emerging as primarily a DSM (demand side management) strategy to encourage energy conservation. Making the electricity grid “smarter” does not:
1. Increase physical transmission capacity;
2. Provide affordable annual-scale firming storage for RE;
3. Solve grid integration problem for large, time-varying RE;
4. Alleviate NIMBY objections to new transmission siting;
5. Reduce the high O&M costs of overhead electric lines. The “smarter” grid may be more vulnerable to cyberattack. Adding storage, control, and quality adjunct devices to the electricity grid, to accommodate very high renewables content, may be technically and economically inferior to GH2 and NH3 RE systems. Thus, we need to look beyond “smart grid”, expanding our concept of “transmission”, to synergistically and simultaneously solve the transmission, firming storage, and RE integration “balancing” problems now severely constraining our progress toward “running the world on renewables”.
On the Nonlinear Dynamics of a Vibro-Impacting Cantilever With End Mass
Authors: Gandhi Prasanna , Badkas Ajinkya 
Published: October 2013

A theoretical and experimental dynamic analysis of a vibro-impacting cantilever with end mass is presented in this paper. The cantilever is excited by transverse harmonic displacement given at its fixed end with the help of a shaker. Nonlinearity in dynamics due to impact of cantilever on a motion limiting stop only on one side is considered.
Experiments revealed quite interesting nonlinear hysteresis, jump, and drop phenomena in this case. Phenomena are experimentally characterized by varying the position and the gap between the stop and cantilever on a custom-built setup. Vibrating cantilever is modeled using assumed modes method while spring damper model for impacting stop is considered. Simulation and experimental results show close match for the same parameters under various cases of stop position and gap. Results are presented in terms of frequency response curves for range of parameters in non-dimensional form to enable their use in similar other cases.
Design and Evaluation of an In-Pipe Leak Detection Sensing Technique Based on Force Transduction
Authors: Chatzigeorgiou Dimitris M. , Ben-Mansour Rached , Khalifa Atia E. , Youcef-Toumi Kamal 
Published: October 2013

Leakage is the major factor for unaccounted fluid losses in almost every pipe network. In most cases the deleterious effects associated with the occurrence of leaks may present serious economical and health problems and therefore, leaks must be quickly detected, located and repaired. The problem of leakage becomes even more serious when it is concerned with the vital supply of fresh water to the community. Leaking water pipelines can develop large health threats to people mostly because of the infiltration of contaminants into the water network. Such possibilities of environmental health disasters have spurred research into the development of methods for pipeline leakage detection.
Most state of the art leak detection techniques have limited applicability, while some of them are not reliable enough and sometimes depend on user experience. Our goal in this work is to design and develop a reliable leak detection sensing system. The proposed technology utilizes the highly localized pressure gradient in the vicinity of a small opening due to leakage in a pressurized pipeline. In this paper we study this local phenomenon in detail and try to understand it with the help of numerical simulations in leaking pipelines (CFD studies). Finally a new system for leak detection is presented.
The proposed system is designed in order to reduce the number of sensing elements required for detection. The main concept and detailed design are laid out. A prototype is fabricated and presented as a proof of concept. The prototype is tested in a simple experimental setup with artificial leakages for experimental evaluation. The sensing technique discussed in this work can be deployed in water, oil and gas pipelines without significant changes in the design, since the concepts remain the same in all cases.
3-D Multibody Modeling of a Flexible Surgical Instrument Inside an Endoscope
Authors: Khatait J. P. , Brouwer D. M. , Meijaard J. P. , Aarts R. G. K. M. , Herder J. L. 
Published: October 2013

Modern surgical procedures involve flexible instruments for both diagnostic and therapeutic purposes. The implementation of flexible instruments in surgery necessitates high motion and force fidelity, and good controllability of the tip. However, the positional accuracy and the force transmission of these instruments are jeopardized by the friction and clearance inside the endoscope, and the compliance of the instrument.
The objective of this paper is to set up a 3-D flexible multibody model for a surgical instrument inside an endoscope to study its translational and rotational behavior. The 3-D model incorporates all the deformations—axial, torsion, and bending—due to its interaction with the surroundings. The interaction due to the contact is defined along the normal and tangential direction at the contact point. The wall stiffness and damping are defined in the normal direction. Friction is defined along the tangential direction. The calculation of the interaction force and moment is explained with an example.
Various simulations were performed to study the behavior of the instrument inside a curved rigid tube. The simulations for the insertion into a 3-D tube defined in a plane were compared for both 2-D and 3-D model. The simulation results from the 3-D model give the same results as the 2-D model. A simulation was carried out for the insertion in a 3-D tube using the 3-D model and the total interaction force on the instrument was analyzed. A 3-D multibody model was set up for the simulation offline rotation. A motion hysteresis of 5° was observed for the chosen configuration.
The 3-D multibody model is able to demonstrate the characteristic behavior of the flexible instrument under different scenarios. Both translational and rotational behavior of the instrument can be characterized for the given set of parameters. The developed model will help us to study the effect of various parameters on the motion and force transmission of the instrument.
Assessment of Embedded Water Needs at a Mixed-Use Facility in Palo Alto, California
Authors: Clayton Mary , Webber Michael E. 
Published: October 2013

Assessing and mitigating the water footprint of a business can reduce the risks associated with potential freshwater shortages. Because water is vital in the supply chain and operations of all major industries, depletion of freshwater sources, increases in demand of water, and droughts can threaten a company’s production, financial stability, and reputation. Consequently, it is essential to identify water vulnerability in a business’s operational portfolio and to ensure that the business’s water management aligns with its overall sustainability strategies. Furthermore, understanding a business’s water footprint allows for effective resource management, which can help minimize costs and reduce its environmental impact.
Currently, interest in the water footprints of organizations, products, and services is increasing, creating a need for a shared standard of definitions and methodologies for water metering and reporting. In addition, consistent methodologies for including embedded and indirect water use and a uniform application of analysis boundaries need to be developed. This research aims to develop an accounting methodology for water reporting along with tools for identifying opportunities to improve water efficiency. Additionally, existing definitions, approaches, and best practices for measuring, reporting, and managing water use across different industries are summarized. A conceptual model was developed to evaluate the lifecycle water footprint, including direct and indirect (embedded in energy and materials) water use in both supply chains and operations. Further, a case study is considered to assess the water impact of a mixed-use facility in Palo, Alto, California. Comprehensive water, electricity, and gas metering data were collected for this site, and the water uses of California’s energy mix were determined. Finally, this data set was utilized to summarize direct and indirect water use at a corporate site, and recommendations of water conservation and reuse for this site are considered. Future work includes development of validation and optimization approaches for minimizing water usage. The model was built such that it can be expanded to include multiple sites in the global supply chain in order to estimate worldwide water usage throughout a large company’s operations.
Potential of Phase Change Material-Enhanced Constructions in Commercial Buildings
Authors: Naimaster Edward J. , Sleiti Ahmad K. 
Published: October 2013

Buildings account for a significant portion of the total energy consumption in the US, especially the energy-inefficient commercial building sector. As part of the future path towards realizing net zero energy buildings, innovative energy-efficient technologies must be developed. In this study, the potential of phase change material (PCM)-enhanced constructions to lower HVAC energy consumption in a commercial building was investigated.
A commercially available fatty acid-based PCM product was selected due promising thermal and chemical properties. Differential scanning calorimetry (DSC) was used in isothermal step mode to accurately measure the latent heat energy storage of the PCM. A US DOE commercial reference building model with a PCM-enhanced ceiling was simulated using a finite-difference conduction heat transfer algorithm in EnergyPlus to determine the effects of the PCM on the building energy performance.
It was found that, although the PCM-enhanced ceiling had a beneficial stabilizing effect on the interior surface temperature of the ceiling, the zone mean air temperatures were not significantly altered. As such, minimal HVAC energy savings were seen. Future work should focus on the potential of active PCM constructions, which could successfully remove stored thermal energy from the PCM without increasing the space cooling energy consumption.
Fatigue Behavior and Microstructure of Pt-20Ir Wire as Lead Conductor in Implantable Medical Device
Authors: Li Bernard Q. , Cho Kailynn , Zhang Haitao 
Published: October 2013

Pt-20Ir cold draw wire has been used as lead conductor in implantable medical devices. The lead is a medical device to transfer the electrical signal from a implanted stimulator to the body area for stimulating such as brain and neurological nerves. In this study, fatigue behavior and failure mechanism of Pt-20Ir wire was studied with rotary bending fatigue testing. The relations between the cyclic strain amplitude (ε) and the cycles to failure (N) were obtained and compared with MP35N wire which is the most commonly used metal wire as lead conductors. The results show Pt-20Ir cold drawn wire (0.102 mm) has a fatigue endurance strain limit of 0.18% which is significant lower than that of MP35N wire.
Microstructure of Pt-20Ir cold draw wire was also analyzed. Results show that the grain size of in wire is elongated like bundled fiber structure. The texture of wire is strongly fiber textured and with a strong gradient from outside layer to center of the wire. Near surface region has <111> textured grain and around center region of the wire has <100> textured grain. The center of grain also has larger size than near surface.
Third-Order Muscle Models: The Role of Oscillatory Behavior in Force Control
Authors: Piovesan Davide , Pierobon Alberto , Mussa-Ivaldi Ferdinando A. 
Published: October 2013

This paper presents the analysis of a third-order linear differential equation representing a muscle-tendon system, including the identification of critical damping conditions.
We analytically verified that this model is required for a faithful representation of muscle-skeletal muscles and provided numerical examples using the biomechanical properties of muscles and tendon reported in the literature.
We proved the existence of a theoretical threshold for the ratio between tendon and muscle stiffness above which critical damping can never be achieved, thus resulting in an oscillatory free response of the system, independently of the value of the damping. Oscillation of the limb can be compensated only by active control, which requires creating an internal model of the limb mechanics.
We demonstrated that, when admissible, over-damping of the muscle-tendon system occurs for damping values included within a finite interval between two separate critical limits. The same interval is a semi-infinite region in second-order models. Moreover, an increase in damping beyond the second critical point rapidly brings the system to mechanical instability.