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2018

Mechanical Engineering Faculty Publications

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Articles 1 - 28 of 28

Full-Text Articles in Mechanical Engineering

Performance Of C2H4 Reductant In Activated-Carbon-Supported Mnox-Based Scr Catalyst At Low Temperatures, Guangli Liu, Dongtai Han, Jie Cheng, Yongshi Feng, Wenbin Quan, Li Yang, Kozo Saito Dec 2018

Performance Of C2H4 Reductant In Activated-Carbon-Supported Mnox-Based Scr Catalyst At Low Temperatures, Guangli Liu, Dongtai Han, Jie Cheng, Yongshi Feng, Wenbin Quan, Li Yang, Kozo Saito

Mechanical Engineering Faculty Publications

Hydrocarbons as reductants show promising results for replacing NH3 in SCR technology. Therefore, considerable interest exists for developing low-temperature (< 200 °C) and environmentally friendly HC-SCR catalysts. Hence, C2H4 was examined as a reductant using activated-carbon-supported MnOx-based catalyst in low-temperature SCR operation. Its sensitivity to Mn concentration and operating temperature was parametrically studied, the results of which showed that the catalyst activity followed the order of 130 °C > 150 °C > 180 °C with an optimized Mn concentration near 3.0 wt.%. However, rapid deactivation of catalytic activity also occurred when using C2H4 as the reductant. The mechanism of deactivation was explored and is …

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Coordinated Unmanned Aircraft System (Uas) And Ground-Based Weather Measurements To Predict Lagrangian Coherent Structures (Lcss), Peter J. Nolan, James Pinto, Javier González-Rocha, Anders Jensen, Christina N. Vezzi, Sean C. C. Bailey, Gijs De Boer, Constantin Diehl, Roger Laurence Iii, Craig W. Powers, Hosein Foroutan, Shane D. Ross, David G. Schmale Iii Dec 2018

Coordinated Unmanned Aircraft System (Uas) And Ground-Based Weather Measurements To Predict Lagrangian Coherent Structures (Lcss), Peter J. Nolan, James Pinto, Javier González-Rocha, Anders Jensen, Christina N. Vezzi, Sean C. C. Bailey, Gijs De Boer, Constantin Diehl, Roger Laurence Iii, Craig W. Powers, Hosein Foroutan, Shane D. Ross, David G. Schmale Iii

Mechanical Engineering Faculty Publications

Concentrations of airborne chemical and biological agents from a hazardous release are not spread uniformly. Instead, there are regions of higher concentration, in part due to local atmospheric flow conditions which can attract agents. We equipped a ground station and two rotary-wing unmanned aircraft systems (UASs) with ultrasonic anemometers. Flights reported here were conducted 10 to 15 m above ground level (AGL) at the Leach Airfield in the San Luis Valley, Colorado as part of the Lower Atmospheric Process Studies at Elevation—a Remotely-Piloted Aircraft Team Experiment (LAPSE-RATE) campaign in 2018. The ultrasonic anemometers were used to collect simultaneous measurements of …

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Opensim Versus Human Body Model: A Comparison Study For The Lower Limbs During Gait, Antoine Falisse, Sam Van Rossom, Johannes Gijsbers, Frans Steenbrink, Ben J. Van Basten, Ilse Jonkers, Antonie J. Van Den Bogert, Friedl De Groote Dec 2018

Opensim Versus Human Body Model: A Comparison Study For The Lower Limbs During Gait, Antoine Falisse, Sam Van Rossom, Johannes Gijsbers, Frans Steenbrink, Ben J. Van Basten, Ilse Jonkers, Antonie J. Van Den Bogert, Friedl De Groote

Mechanical Engineering Faculty Publications

Musculoskeletal modeling and simulations have become popular tools for analyzing human movements. However, end users are often not aware of underlying modeling and computational assumptions. This study investigates how these assumptions affect biomechanical gait analysis outcomes performed with Human Body Model and the OpenSim gait2392 model. The authors compared joint kinematics, kinetics, and muscle forces resulting from processing data from 7 healthy adults with both models. Although outcome variables had similar patterns, there were statistically significant differences in joint kinematics (maximal difference: 9.8 degrees {[}1.5 degrees] in sagittal plane hip rotation), kinetics (maximal difference: 0.36 {[}0.10] N.m/kg in sagittal plane …

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Cfd Modeling On Hydrodynamic Characteristics Of Multiphase Counter-Current Flow In A Structured Packed Bed For Post-Combustion Co2 Capture, Li Yang, Fang Liu, Kozo Saito, Kunlei Liu Nov 2018

Cfd Modeling On Hydrodynamic Characteristics Of Multiphase Counter-Current Flow In A Structured Packed Bed For Post-Combustion Co2 Capture, Li Yang, Fang Liu, Kozo Saito, Kunlei Liu

Mechanical Engineering Faculty Publications

Solvent-based post combustion CO2 capture is a promising technology for industrial application. Gas-liquid interfaces and interactions in the packed bed are considered one of the key factors affecting the overall CO2 absorption rate. Understanding the hydrodynamic characterizations within packed beds is essential to identify the appropriate enhanced mass transfer technique. However, multiphase counter-current flows in the structured packing typically used in these processes are complicated to visualize and optimize experimentally. In this paper, we aim to develop a comprehensive 3D multiphase, counter-current flow model to study the liquid/gas behavior on the surface of structured packing. The output from …

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Capturing The Competing Influence Of Thermal And Mechanical Loads On The Strain Of Turbine Blade Coatings Via High Energy X-Rays, Albert Manero, Kevin Knipe, Janine Wischek, Carla Meid, John Okasinski, Jonathan Almer, Anette M. Karlsson, Marion Bartsch, Seetha Raghavan Sep 2018

Capturing The Competing Influence Of Thermal And Mechanical Loads On The Strain Of Turbine Blade Coatings Via High Energy X-Rays, Albert Manero, Kevin Knipe, Janine Wischek, Carla Meid, John Okasinski, Jonathan Almer, Anette M. Karlsson, Marion Bartsch, Seetha Raghavan

Mechanical Engineering Faculty Publications

This paper presents findings of synchrotron diffraction measurements on tubular specimens with a thermal barrier coating (TBC) system applied by electron beam physical vapor deposition (EB-PVD), having a thermally grown oxide (TGO) layer due to aging in hot air. The diffraction measurements were in situ while applying a thermal cycle with high temperature holds at 1000 °C and varying internal air cooling mass flow and mechanical load. It was observed that, during high temperature holds at 1000 °C, the TGO strain approached zero if no mechanical load or internal cooling was applied. When applying a mechanical load, the TGO in-plane …

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Assessing Production Line Risk Using Bayesian Belief Networks And System Dynamics, Sudhir Punyamurthula, Fazleena Badurdeen Aug 2018

Assessing Production Line Risk Using Bayesian Belief Networks And System Dynamics, Sudhir Punyamurthula, Fazleena Badurdeen

Mechanical Engineering Faculty Publications

Increased complexity in product design, strict regulations and a changing market make risk assessment critical for successful operations. Failure in responding quickly to raw material shortages, downtimes, deteriorating equipment conditions or other operational issues can prove to be an expensive affair. A company-wide risk assessment includes both external and internal operations. However, external/supplier risk assessment has been of major interest. Even though the scope of risk assessment at the production line level is not as broad as it is at the supply chain level, assessing risk would help recognize vulnerable areas of the production line, which would in turn help …

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An Efficient Constructive Heuristic To Balance Trade-Offs Between Makespan And Flowtime In Permutation Flow Shop Scheduling, Feidi Dang, Wei Li, Honghan Ye Aug 2018

An Efficient Constructive Heuristic To Balance Trade-Offs Between Makespan And Flowtime In Permutation Flow Shop Scheduling, Feidi Dang, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Balancing trade-offs between production cost and holding cost is critical for production and operations management. Utilization of a production line affects production cost, which relates to makespan, and work-in-process (WIP) inventories in a production line affect holding cost, which relate to flowtime. There are trade-offs between two objectives, to minimize makespan and to minimize flowtime. Without addressing trade-off balancing issues in flow shop scheduling, WIP inventories are still high in manufacturing, generating unnecessary holding cost. However, utilization is coupled with WIP inventories. Low WIP inventory levels might lower utilization and generate high production cost. Most existing constructive heuristics focus only …

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Low-Cost Experimental System For Center Of Mass And Center Of Pressure Measurement, Cai Xia Yang Aug 2018

Low-Cost Experimental System For Center Of Mass And Center Of Pressure Measurement, Cai Xia Yang

Mechanical Engineering Faculty Publications

Falls happen when the center of mass of body is outside of its base of support and the recovery of the center of mass back to the base of support failed. Balance ability is an essential ability needed for humans' daily routine activities. Improving balance ability should result in a better and more convenient way of living. There are various factors influence on balance ability. The focus of this paper is to investigate which factors have the greatest effect on balance. Balance ability is measured by deviations of center of pressure in both x-direction (side-to-side) and y-direction (front-to-back) with the …

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Considerations For Atmospheric Measurements With Small Unmanned Aircraft Systems, Jamey D. Jacob, Phillip B. Chilson, Adam L. Houston, Suzanne Weaver Smith Jul 2018

Considerations For Atmospheric Measurements With Small Unmanned Aircraft Systems, Jamey D. Jacob, Phillip B. Chilson, Adam L. Houston, Suzanne Weaver Smith

Mechanical Engineering Faculty Publications

This paper discusses results of the CLOUD-MAP (Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics) project dedicated to developing, fielding, and evaluating integrated small unmanned aircraft systems (sUAS) for enhanced atmospheric physics measurements. The project team includes atmospheric scientists, meteorologists, engineers, computer scientists, geographers, and chemists necessary to evaluate the needs and develop the advanced sensing and imaging, robust autonomous navigation, enhanced data communication, and data management capabilities required to use sUAS in atmospheric physics. Annual integrated evaluation of the systems in coordinated field tests are being used to validate sensor performance while integrated into various sUAS platforms. …

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Compensation For Inertial And Gravity Effects In A Moving Force Platform, Sandra K. Hnat, Ben J.H. Van Basten, Antonie J. Van Den Bogert Jun 2018

Compensation For Inertial And Gravity Effects In A Moving Force Platform, Sandra K. Hnat, Ben J.H. Van Basten, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

Force plates for human movement analysis provide accurate measurements when mounted rigidly on an inertial reference frame. Large measurement errors occur, however, when the force plate is accelerated, or tilted relative to gravity. This prohibits the use of force plates in human perturbation studies with controlled surface movements, or in conditions where the foundation is moving or not sufficiently rigid. Here we present a linear model to predict the inertial and gravitational artifacts using accelerometer signals. The model is first calibrated with data collected from random movements of the unloaded system and then used to compensate for the errors in …

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Uat Ads-B Data Anomalies And The Effect Of Flight Parameters On Dropout Occurrences, Asma Tabassum, William Semke Jun 2018

Uat Ads-B Data Anomalies And The Effect Of Flight Parameters On Dropout Occurrences, Asma Tabassum, William Semke

Mechanical Engineering Faculty Publications

An analysis of the performance of automatic dependent surveillance-broadcast (ADS-B) data received from the Grand Forks, North Dakota International Airport was carried out in this study. The purpose was to understand the vulnerabilities of the universal access transceiver (UAT) ADS-B system and recognize the effects on present and future air traffic control (ATC) operation. The Federal Aviation Administration (FAA) mandated all the general aviation aircraft to be equipped with ADS-B. The aircraft flying within United States and below the transition altitude (18,000 feet) are more likely to install a UAT ADS-B. At present, unmanned aircraft systems (UAS) and autonomous air …

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3d Numerical Study Of Multiphase Counter-Current Flow Within A Packed Bed For Post Combustion Carbon Dioxide Capture, Li Yang, Fang Liu, Zhengchang Song, Kunlei Liu, Kozo Saito Jun 2018

3d Numerical Study Of Multiphase Counter-Current Flow Within A Packed Bed For Post Combustion Carbon Dioxide Capture, Li Yang, Fang Liu, Zhengchang Song, Kunlei Liu, Kozo Saito

Mechanical Engineering Faculty Publications

The hydrodynamics within counter-current flow packed beds is of vital importance to provide insight into the design and operational parameters that may impact reactor and reaction efficiencies in processes used for post combustion CO2 capture. However, the multiphase counter-current flows in random packing used in these processes are complicated to visualize. Hence, this work aimed at developing a computational fluid dynamics (CFD) model to study more precisely the complex details of flow inside a packed bed. The simulation results clearly demonstrated the development of, and changes in, liquid distributions, wetted areas, and film thickness under various gas and liquid …

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Fracture Initiation In A Transversely Isotropic Solid: Transient Three Dimensional Analysis, Louis Milton Brock May 2018

Fracture Initiation In A Transversely Isotropic Solid: Transient Three Dimensional Analysis, Louis Milton Brock

Mechanical Engineering Faculty Publications

A transversely isotropic solid is at rest, and contains a semi-infinite, plane crack. The axis of rotational material symmetry lies in the crack plane. Application of normal point forces to each face of the crack causes transient 3D growth. The related problem of discontinuities in displacement and traction that exist on regions that exhibit dynamic similarity is first considered. Analytic results are obtained in integral transform space. These lead to equations of the Wiener–Hopf type for the fracture problem. Analytic solutions are again obtained and, upon inversion, subjected to a dynamic energy release rate criterion that includes kinetic energy. A …

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Research And Development Of Powder Brazing Filler Metals For Diamond Tools: A Review, Fei Long, Peng He, Dusan P. Sekulic May 2018

Research And Development Of Powder Brazing Filler Metals For Diamond Tools: A Review, Fei Long, Peng He, Dusan P. Sekulic

Mechanical Engineering Faculty Publications

Powder brazing filler metals (PBFMs) feature a number of comparative advantages. Among others, these include a low energy consumption, an accurate dosage, a good brazeability, a short production time, and a high production efficiency. These filler metals have been used in the aerospace, automobile, and electric appliances industries. The PBFMs are especially suitable for diamond tools bonding, which involves complex workpiece shapes and requires accurate dosage. The recent research of PBFMs for diamond tools is reviewed in this paper. The current applications are discussed. The CuSnTi and Ni-Cr-based PBFMs have been the two commonly used monolayer PBFMs. Thus, the bonding …

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Study Of Near-Cup Droplet Breakup Of An Automative Electrostatic Rotary Bell (Esrb) Atomizer Using High-Speed Shadowgraph Imaging, Jacob E. Wilson, Stephen William Grib, Adnan Darwish Ahmad, Michael W. Renfro, Scott A. Adams, Ahmad Salaimeh May 2018

Study Of Near-Cup Droplet Breakup Of An Automative Electrostatic Rotary Bell (Esrb) Atomizer Using High-Speed Shadowgraph Imaging, Jacob E. Wilson, Stephen William Grib, Adnan Darwish Ahmad, Michael W. Renfro, Scott A. Adams, Ahmad Salaimeh

Mechanical Engineering Faculty Publications

Electrostatic Rotary bell (ESRB) atomizers are used as the dominant means of paint application by the automotive industry. They utilize the high rotational speed of a cup to induce primary atomization of a liquid along with shaping air to provide secondary atomization and transport. In order to better understand the fluid breakup mechanisms involved in this process, high-speed shadowgraph imaging was used to visualize the edge of a serrated rotary bell at speeds varying between 5000 and 12,000 RPM and with a water flow rate of 250 ccm. A multi-step image processing algorithm was developed to differentiate between ligaments and …

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Evaluation Of A Novel Finite Element Model Of Active Contraction In The Heart, Xiaoyan Zhang, Zhan-Qiu Liu, Kenneth S. Campbell, Jonathan F. Wenk Apr 2018

Evaluation Of A Novel Finite Element Model Of Active Contraction In The Heart, Xiaoyan Zhang, Zhan-Qiu Liu, Kenneth S. Campbell, Jonathan F. Wenk

Mechanical Engineering Faculty Publications

Finite element (FE) modeling is becoming a widely used approach for the investigation of global heart function. In the present study, a novel model of cellular-level systolic contraction, which includes both length- and velocity-dependence, was implemented into a 3D non-linear FE code. To validate this new FE implementation, an optimization procedure was used to determine the contractile parameters, associated with sarcomeric function, by comparing FE-predicted pressure and strain to experimental measures collected with magnetic resonance imaging and catheterization in the ventricles of five healthy rats. The pressure-volume relationship generated by the FE models matched well with the experimental data. Additionally, …

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Scalable Patterning Using Laser-Induced Shock Waves, Saidjafarzoda Ilhom, Khomidkhodza Kholikov, Peizhen Li, Claire Ottman, Dylan Sanford, Zachary Thomas, Omer San, Haluk E. Karaca, Ali O. Er Apr 2018

Scalable Patterning Using Laser-Induced Shock Waves, Saidjafarzoda Ilhom, Khomidkhodza Kholikov, Peizhen Li, Claire Ottman, Dylan Sanford, Zachary Thomas, Omer San, Haluk E. Karaca, Ali O. Er

Mechanical Engineering Faculty Publications

An advanced direct imprinting method with low cost, quick, and minimal environmental impact to create a thermally controllable surface pattern using the laser pulses is reported. Patterned microindents were generated on Ni50Ti50 shape memory alloys and aluminum using an Nd: YAG laser operating at 1064 nm combined with a suitable transparent overlay, a sacrificial layer of graphite, and copper grid. Laser pulses at different energy densities, which generate pressure pulses up to a few GPa on the surface, were focused through the confinement medium, ablating the copper grid to create plasma and transferring the grid pattern onto …

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Optimal Mixed Tracking/Impedance Control With Application To Transfemoral Prostheses With Energy Regeneration, Gholamreza Khademi, Hanieh Mohammadi, Hanz Richter, Daniel J. Simon Apr 2018

Optimal Mixed Tracking/Impedance Control With Application To Transfemoral Prostheses With Energy Regeneration, Gholamreza Khademi, Hanieh Mohammadi, Hanz Richter, Daniel J. Simon

Mechanical Engineering Faculty Publications

We design an optimal passivitybased tracking/impedance control system for a robotic manipulator with energy regenerative electronics, where the manipulator has both actively and semi-actively controlled joints. The semi-active joints are driven by a regenerative actuator that includes an energy-storing element. Method: External forces can have a large influence on energy regeneration characteristics. Impedance control is used to impose a desired relationship between external forces and deviation from reference trajectories. Multi-objective optimization (MOO) is used to obtain optimal impedance parameters and control gains to compromise between the two conflicting objectives of trajectory tracking and energy regeneration. We solve the MOO problem …

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Modeling Of Nitihf Using Finite Difference Method, Nazanin Farjam, Reza Mehrabi, Haluk E. Karaca, Reza Mirzaeifar, Mohammad Elahinia Mar 2018

Modeling Of Nitihf Using Finite Difference Method, Nazanin Farjam, Reza Mehrabi, Haluk E. Karaca, Reza Mirzaeifar, Mohammad Elahinia

Mechanical Engineering Faculty Publications

NiTiHf is a high temperature and high strength shape memory alloy with transformation temperatures above 100oC. A constitutive model based on Gibbs free energy is developed to predict the behavior of this material. Two different irrecoverable strains including transformation induced plastic strain (TRIP) and viscoplastic strain (VP) are considered when using high temperature shape memory alloys (HTSMAs). The first one happens during transformation at high levels of stress and the second one is related to the creep which is rate-dependent. The developed model is implemented for NiTiHf under uniaxial loading. Finite difference method is utilized to solve the proposed equations. …

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Selective Laser Melting Of Ni-Rich Niti: Selection Of Process Parameters And The Superelastic Response, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ehsan Saghaian, Ahmadreza Jahadakbar, Haluk E. Karaca, Mohammad Elahinia Mar 2018

Selective Laser Melting Of Ni-Rich Niti: Selection Of Process Parameters And The Superelastic Response, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ehsan Saghaian, Ahmadreza Jahadakbar, Haluk E. Karaca, Mohammad Elahinia

Mechanical Engineering Faculty Publications

Material and mechanical properties of NiTi shape memory alloys strongly depend on the fabrication process parameters and the resulting microstructure. In selective laser melting, the combination of parameters such as laser power, scanning speed, and hatch spacing determine the microstructural defects, grain size and texture. Therefore, processing parameters can be adjusted to tailor the microstructure and mechanical response of the alloy. In this work, NiTi samples were fabricated using Ni50.8Ti (at.%) powder via SLM PXM by Phenix/3D Systems and the effects of processing parameters were systematically studied. The relationship between the processing parameters and superelastic properties were investigated …

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Influence Of Slm On Compressive Response Of Niti Scaffolds, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ahmadreza Jahadakbar, Sayed Ehsan Saghaian, Haluk E. Karaca, Mohammad Elahinia Mar 2018

Influence Of Slm On Compressive Response Of Niti Scaffolds, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ahmadreza Jahadakbar, Sayed Ehsan Saghaian, Haluk E. Karaca, Mohammad Elahinia

Mechanical Engineering Faculty Publications

Porous Nickel-Titanium shape memory alloys (NiTi-SMAs) have attracted much attention in biomedical applications due to their high range of pure elastic deformability (i.e., superelasticity) as well as their bone-level modulus of elasticity (E≈12-20 GPa). In recent years, Selective Laser Melting (SLM) has been used to produce complex NiTi components. The focus of this study is to investigate the superelasticity and compressive properties of SLM NiTi-SMAs. To this aim, several NiTi components with different level of porosities (32- 58%) were fabricated from Ni50.8Ti (at. %) powder via SLM PXM by Phenix/3D Systems, using optimum processing parameter (Laser power-P=250 W, …

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Experimental Examination Of Vorticity Stripping From A Wing-Tip Vortex In Free-Stream Turbulence, Hari C. Ghimire, Sean C. C. Bailey Mar 2018

Experimental Examination Of Vorticity Stripping From A Wing-Tip Vortex In Free-Stream Turbulence, Hari C. Ghimire, Sean C. C. Bailey

Mechanical Engineering Faculty Publications

Time-resolved stereoscopic particle image velocimetry measurements were conducted of a wing-tip vortex decaying in free-stream turbulence. The objective of the research was to experimentally investigate the mechanism causing the increased rate of decay of the vortex in the presence of turbulence. It was observed that the circulation of the vortex core experienced periods of rapid loss and recovery when immersed in free-stream turbulence. These events were not observed when the vortex was in a laminar free stream. A connection was made between these events and distortion of the vortex, coinciding with stripping of core fluid from the vortex core. Specifically, …

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Formation Of Two-Way Shape Memory Effect In Niti Alloy Using Pulsed Laser Irradiation, Saidjafarzoda Ilhom, Khomidkhodza Kholikov, Peizhen Li, Dovletgeldi Seyitliyev, Zachary Thomas, Duvall Roberts, Omer San, Haluk E. Karaca, Ali O. Er Feb 2018

Formation Of Two-Way Shape Memory Effect In Niti Alloy Using Pulsed Laser Irradiation, Saidjafarzoda Ilhom, Khomidkhodza Kholikov, Peizhen Li, Dovletgeldi Seyitliyev, Zachary Thomas, Duvall Roberts, Omer San, Haluk E. Karaca, Ali O. Er

Mechanical Engineering Faculty Publications

Shape memory alloys (SMAs) are a unique class of smart materials and they were employed in various applications in engineering, biomedical, and aerospace technologies. Here, we report an advanced, efficient, and low-cost direct imprinting method with low environmental impact to create thermally controllable surface patterns. Patterned microindents were generated on Ni50Ti50 (at. %) SMAs using an Nd:YAG laser with 1064 nm wavelength at 10 Hz. Laser pulses at selected fluences were focused on the NiTi surface and generated pressure pulses of up to a few GPa. Optical microscope images showed that surface patterns with tailorable sizes can …

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Opty: Software For Trajectory Optimization And Parameter Identification Using Direct Collocation, Jason K. Moore, Antonie J. Van Den Bogert Jan 2018

Opty: Software For Trajectory Optimization And Parameter Identification Using Direct Collocation, Jason K. Moore, Antonie J. Van Den Bogert

Mechanical Engineering Faculty Publications

opty is a tool for describing and solving trajectory optimization and parameter identification problems based on symbolic descriptions of ordinary differential equations and differential algebraic equations that describe a dynamical system. The motivation for its development resides in the need to solve optimal control problems of biomechanical systems. The target audience is engineers and scientists interested in solving nonlinear optimal control and parameter identification problems with minimal computational overhead.

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Sustainable Living Factories For Next Generation Manufacturing, Yoram Koren, Xi Gu, Fazleena Badurdeen, Ibrahim S. Jawahir Jan 2018

Sustainable Living Factories For Next Generation Manufacturing, Yoram Koren, Xi Gu, Fazleena Badurdeen, Ibrahim S. Jawahir

Mechanical Engineering Faculty Publications

To be profitable and to generate sustainable value for all stakeholders, next generation manufacturers must develop capabilities to rapidly and economically respond to changing market needs while at the same time minimizing adverse impacts on the environment and benefiting society. 6R-based (Reduce, Reuse, Recycle, Recover, Redesign and Remanufacturing) sustainable manufacturing practices enable closed-loop and multi-life cycle material flow; they facilitate producing more sustainable products using manufacturing processes and systems that are more sustainable. Reconfigurable Manufacturing Systems (RMS) and its characteristics of scalability, convertibility, diagnosability, customization, modularity and integrability have emerged as a basis for living factories for next generation manufacturing …

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Stochastic Bi-Level Optimization Models For Efficient Operating Room Planning, Amin Abedini, Wei Li, Honghan Ye Jan 2018

Stochastic Bi-Level Optimization Models For Efficient Operating Room Planning, Amin Abedini, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Within a hospital, the operating room (OR) department has the largest cost and revenue. Because of the aging population, the demand for surgical services has been increasing sharply in recent years. At the other hand, the rate of OR capacity expansion is lower than the rate of increasing demand. As a result, OR managers must leverage their resources by efficient OR planning. OR planning is challenging because of multiple competing\conflicting objectives such cost minimization and throughput maximization. Inherent uncertainty in the surgical procedures and patients arrivals complicate the decision making process. This increases the risk of non-realization of the system …

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Towards Developing Sustainable Reconfigurable Manufacturing Systems, Aihua Huang, Fazleena Badurdeen, Ibrahim S. Jawahir Jan 2018

Towards Developing Sustainable Reconfigurable Manufacturing Systems, Aihua Huang, Fazleena Badurdeen, Ibrahim S. Jawahir

Mechanical Engineering Faculty Publications

This paper aims to examine the sustainable manufacturing performance of Reconfigurable Manufacturing Systems (RMSs) using existing sustainable manufacturing metrics. RMS has six key characteristics including modularity, integrability, customization, scalability, convertibility, and diagnosability. In this paper, ‘convertibility’ is quantified by considering configuration convertibility, machine convertibility, and material handling device convertibility from the RMS perspective. In addition, the performance of RMSs with different convertibility levels is also evaluated by using sustainable manufacturing metrics. A numerical example is used to demonstrate the computational approach. Results of the analysis are used to show how sustainable manufacturing performance of RMS changes as system convertibility varies. …

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Bidirectionally Stretched Flow Of Jeffrey Liquid With Nanoparticles, Rosseland Radiation And Variable Thermal Conductivity, M. Archana, B. J. Gireesha, M. M. Rashidi, B. C. Prasannakumara, Rama S.R. Gorla Jan 2018

Bidirectionally Stretched Flow Of Jeffrey Liquid With Nanoparticles, Rosseland Radiation And Variable Thermal Conductivity, M. Archana, B. J. Gireesha, M. M. Rashidi, B. C. Prasannakumara, Rama S.R. Gorla

Mechanical Engineering Faculty Publications

Heat and mass transfer stretched flow of an incompressible, electrically conducting Jeffrey fluid has been studied numerically. Nanoparticles are suspended in the base fluid and it has many applications such as cooling of engines, thermal absorption systems, lubricants fuel cell, nanodrug delivery system and so on. Temperature dependent variable thermal conductivity with Rosseland approximation is taken into account and suction effect is employed in the boundary conditions. The governing partial differential equations are first transformed into set of ordinary differential equations using selected similarity transformations, which are then solved numerically using Runge-Kutta-Felhberg fourth-fifth order method along with shooting technique. The …

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