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Full-Text Articles in Engineering
Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang
Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang
Electronic Theses and Dissertations
Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …
Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari
Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari
Electronic Theses and Dissertations
Extrusion-based 3D printing of thermoplastic polymer composites manufactures parts that have nonhomogenous, orthotropic, and process-dependent macro-scale material properties. As a part of the dissertation, research works were carried out to: • improve the interlayer mechanical properties and reduce the orthotropy, • use experimentally homogenized orthotropic material properties to numerically model the mechanical behavior of the non-homogenous orthotropic 3D printed parts, • create an efficient numerical thermal model to predict the process-dependent thermal history of the 3D printed part, and • aid the manufacturing process by selecting a suitable set of processing parameters based on a simplified sequentially coupled thermomechanical model. …
Impact Of Magnetocaloric Material Properties On Performance Of A Magnetocaloric Heat Pump., Michael G. Schroeder
Impact Of Magnetocaloric Material Properties On Performance Of A Magnetocaloric Heat Pump., Michael G. Schroeder
Electronic Theses and Dissertations
In the field of magnetocaloric heat pumps much research has been performed around machine design and theoretical machines, but little has been researched around practical problems such as variability in material properties. The present work defines a simulation tool that has been proven with experimental data. Magnetocaloric material cascades were statistically analyzed and parameterized, such that they could be recreated parametrically using a split Lorentz function with normally distributed parameters. Correlated curve-defining values with standard deviations were used as input into the simulation tool to determine the effect of variation on cooling heat pump performance for a household refrigerator application. …
Modeling, Simulation, And Validation Of Process-Structure-Property Relationships In Fused Filament Fabrication, Aaron Grant
Modeling, Simulation, And Validation Of Process-Structure-Property Relationships In Fused Filament Fabrication, Aaron Grant
Electronic Theses and Dissertations
As additive manufacturing (AM) grows in popularity, the need for better simulation tools to predict the process-structure-property relationships of AM parts becomes ever more necessary to employ the technology in design of functional parts with varying degrees of complexity and performance requirements. Many simulation tools and techniques have been developed that aim to achieve this goal, and the main purpose of this research is to explore how well different simulation tools and modeling approaches can capture various AM-specific features such as inter-raster and end-of raster voids, and residual stresses induced by dissimilar rates of thermal expansion. Process simulation of fused …
Modeling And Simulation Of The Thermoforming Process In Thermoplastic-Matrix Composite Materials, Philip M. Bean
Modeling And Simulation Of The Thermoforming Process In Thermoplastic-Matrix Composite Materials, Philip M. Bean
Electronic Theses and Dissertations
Thermoplastic-matrix composite materials have unique advantages over traditional thermosets including faster processing, improved fracture toughness, and recyclability. These and other benefits have caused increasing interest in the use of these materials in both aerospace and automotive industries. Due to the differences in behavior, these materials require a different type of manufacturing process to thermoset matrix composites. This manufacturing process generally involves using pre manufactured tape-layers. These layers, containing both thermoplastic-matrix and fiber-reinforcement, are aligned to the desired orientation, and stacked up into a “tailored blank” using an automated tape layup machine. They are then heated to the thermoplastic melting temperature …
Translating Data From The Laboratory Into Simulation: A Computational Framework For Subject-Specific Finite Element Musculoskeletal Simulation, Donald R. Hume
Translating Data From The Laboratory Into Simulation: A Computational Framework For Subject-Specific Finite Element Musculoskeletal Simulation, Donald R. Hume
Electronic Theses and Dissertations
Computational modeling is a powerful tool which has been used to inform decisions made by engineers, scientists, and clinicians for decades. Musculoskeletal modeling has emerged as a computational modeling technique used to understand the interaction between the body and its surroundings. There are several common approaches used for musculoskeletal modeling which take advantage of different model formulations to obtain information of interest. Unfortunately, models with different joint formulations inherit disparities in representations of ligament, muscle, and cartilage at joints of interest. These differences affect the way the joint functions and limit the insight it provides through computational analysis. Musculoskeletal models …
Simulation Of An Ethylene Flame With Turbulence, Soot And Radiation Modeling, Santu Golder
Simulation Of An Ethylene Flame With Turbulence, Soot And Radiation Modeling, Santu Golder
Electronic Theses and Dissertations
This thesis will investigate soot models that are available in commercial codes. We will look at the effect of turbulence models, gravity, soot models and radiation. Simulations will be compared to Coppalle and Joyeux [1]. The flame is an ethylene air diffusion flame at a Reynolds number of 5700. Simulations show the SST turbulence model, one-step soot model and Rosseland radiation model including gravity agree well with experimental data (temperature and soot). Flamelet soot modeling from Carbonell et al. [2] and flamelet radiation modeling from Doom [3] has been incorporated and compared as well.
Material Properties Design Using Simulations And Experiments For Powder Injection Molding Of Lead Zirconate Titanate (Pzt)., Bhushan Pramod Bandiwadekar
Material Properties Design Using Simulations And Experiments For Powder Injection Molding Of Lead Zirconate Titanate (Pzt)., Bhushan Pramod Bandiwadekar
Electronic Theses and Dissertations
Powder injection molding (PIM) process simulations can be performed to minimize the number of injection molding experiments by estimating material properties necessary for PIM simulations. In current work, lead zirconate titanate (PZT) powder-polymer binder feedstock was compounded for 45 vol. % and 52 vol. % solids loading. PIM experiments on designed micro-pillar array geometry were performed using 52 vol. % PZT. Using PIM experiments results as basis, PIM simulations were performed on designed micro-pillar array geometries to understand the effectiveness of PIM simulations with the use of estimated feedstock properties in predicting molding behavior that have micro-features. Additionally, PIM simulations …
Combustion Kinetics Of Advanced Biofuels, Ghazal Barari
Combustion Kinetics Of Advanced Biofuels, Ghazal Barari
Electronic Theses and Dissertations
Use of biofuels, especially in automotive applications, is a growing trend due to their potential to lower greenhouse gas emissions from combustion. Ketones are a class of biofuel candidates which are produced from cellulose. However, ketones received rather scarce attention from the combustion community compared to other classes such as, alcohols, esters, and ethers. There is little knowledge on their combustion performance and pollutant generation. Hence their combustion chemistry needs to be investigated in detail. Diisopropyl ketone (DIPK) is a promising biofuel candidate, which is produced using endophytic fungal conversion. A detailed understanding of the combustion kinetics of the oxidation …