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Product Development Of License Plate Holder : In Collaboration With Koenigsegg Automotive ABGustavsson, Sofia, Oschmann, Adelina January 2023 (has links)
This report is being conducted in collaboration with Koenigsegg Automotive AB, a company founded in 1994 that manufactures mega cars. This study aims to design a license plate holder for their new car Jesko that comes in two models, Absolut and Track. The license plate holder is to be adapted to a specific country and their regulatory framework. The project also involves selecting materials and manufacturing processes in consultation with the industrial partner. The work has been divided into different stages, calculations, CAD modeling, analysis, and selection of materials and manufacturing processes. The CAD modeling is performed using Catia V5, while the analyses are conducted using SimSolid. The methodology used in this project is inspired by the method outlined in the book "Product Design and Development" by Karl T. Ulrich, Steven D. Eppinger, and Maria C. Yang. The method consists of six main steps: planning, research, customer needs, concept generation, concept selection, and detailed design. The result chose six different concepts being developed, analyzed, and compared. After identifying the most suitable concept, it is presented with a detailed product description of its design, materials, and manufacturing methods. This report is being conducted in collaboration with Koenigsegg Automotive AB, a company founded in 1994 that manufactures mega cars. This study aims to design a license plate holder for their new car Jesko that comes in two models, Absolut and Track. The license plate holder is to be adapted to a specific country and their regulatory framework. The project also involves selecting materials and manufacturing processes in consultation with the industrial partner. The work has been divided into different stages, calculations, CAD modeling, analysis, and selection of materials and manufacturing processes. The CAD modeling is performed using Catia V5, while the analyses are conducted using SimSolid. The methodology used in this project is inspired by the method outlined in the book "Product Design and Development" by Karl T. Ulrich, Steven D. Eppinger, and Maria C. Yang. The method consists of six main steps: planning, research, customer needs, concept generation, concept selection, and detailed design. The result chose six different concepts being developed, analyzed, and compared. After identifying the most suitable concept, it is presented with a detailed product description of its design, materials, and manufacturing methods.
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Internal State Variable Plasticity-Damage Modeling of AISI 4140 Steel Including Microstructure-Property Relations: Temperature and Strain Rate EffectsNacif el Alaoui, Reda 09 December 2016 (has links)
Mechanical structure-property relations have been quantified for AISI 4140 steel under different strain rates and temperatures. The structure-property relations were used to calibrate a microstructure-based internal state variable plasticity-damage model for monotonic tension, compression and torsion plasticity, as well as damage evolution. Strong stress state and temperature dependences were observed for the AISI 4140 steel. Tension tests on three different notched Bridgman specimens were undertaken to study the damage-triaxiality dependence for model validation purposes. Fracture surface analysis was performed using Scanning Electron Microscopy (SEM) to quantify the void nucleation and void sizes in the different specimens. The stress-strain behavior exhibited a fairly large applied stress state (tension, compression dependence, and torsion), a moderate temperature dependence, and a relatively small strain rate dependence.
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Sheet-stamping process simulation and optimizationTamasco, Cynthia M 06 August 2011 (has links)
This thesis presents the development and implementation of a generalized optimization framework for use in sheet-stamping process simulation by finite element analysis. The generic framework consists of three main elements: a process simulation program, an optimization code, and a response filtering program. These elements can be filled by any combination of applicable software packages. Example sheet-stamping process simulations are presented to demonstrate the usage of the framework in various forming scenarios. Each of the example simulations is presented with a sensitivity analysis. These examples include analysis of a 2-dimensional single-stage forming, a 2-dimensional multi-stage forming, and two different 3-dimensional single-stage forming processes. A forming limit diagram is used to define failure in the 3-dimensional process simulations. Optimization results are presented using damage minimization, thinning minimization, and springback minimization with aluminum alloy 6061-T6 blanks.
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Three Dimensional Elasticity Analyses for Isotropic and Orthotropic Composite CylindersWang, Wenchao 12 May 2012 (has links)
The demand for using shell theories comes from its efficiency in computational and analytical cost. On another side, new materials that are orthotropic and/or anisotropic in nature are discovered and broadly used in many fields. Many advanced shell theories are developed for these new materials, particularly in the recent decades. A study about the accuracy of these shell theories is very meaningful to build confidence in them for further applications. This study requires a precise benchmark against which shell theories can be tested. This is the main research subjective in this dissertation: to build a set of solutions using the three dimensional (3D) theory of elasticity against which shell theories can be tested for accuracy. The contents of this dissertation to support this research include a comprehensive literature review for the shell theories and recent usage and to find the gaps which need to be filled. These gaps include, among others, the lack of studies on the accuracy of the theories used and the absence of results using the 3D theory, particularly for orthotropic materials. Some of these studies are conducted here. The deficiency of some commercial finite element packages is discussed here. The reasons for the absence of accurate results are investigated. The 3D theory and analyses of isotropic and orthotropic materials of hollow cylinders is investigated here for reliable results.
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Testing and Thermal Management System Design of an Ultra-Fast Charging Battery Module for Electric Vehicles / Battery Module Thermal Management System DesignZhao, Ziyu January 2021 (has links)
This thesis consists of three main objectives: fundamental and literature review of EV batteries, experimental development, and validation of two liquid cooling battery modules, thermal modeling and comparison of the inter-cell cooling battery module. / The traditional vehicles with internal combustion engine have resulted in severe environmental pollution, which motivates the development of electric vehicles and hybrid electric vehicles. Due to a low energy density and long refueling time of the battery pack, it is still hard for electric vehicles and hybrid electric vehicles to be widely accepted by the consumers. As the batteries with a better ultra-fast charging capability are massively produced, the range anxiety issue is somewhat alleviated.
During a charging with large current magnitude, the battery generally has a great amount of heat generation and evident temperature rise. Therefore, a thermal management system is necessary to effectively dissipate the battery loss and minimize the degradation mechanisms caused by extreme temperature. The motivation of this thesis is to study the discipline of the battery thermal management system as an application for electric vehicles. The design methodologies are presented in both experiment test and numerical simulation.
For the comparative study between active liquid cooling methods for a lithium-ion battery module using experimental techniques, two battery modules with three Kokam Nickel Manganese Cobalt battery cells connected in parallel are developed. One has liquid coolant flowing along the edge of the model, and another with liquid coolant flowing between the cells. Several characterization tests, including thermal resistance tests, fast charging tests up to 5C, and drive cycle tests are designed and performed on the battery module. The inter-cell cooling module has a lower peak temperature rise and faster thermal response compared to the edge cooling module, i.e., 4.1⁰C peak temperature rise under 5C charging for inter-cell cooling method and 14.2⁰C for edge cooling method.
The thermal models built in ANSYS represent the numerical simulation of the inter-cell cooling module as a comparison with the experiment. A cell loss model is developed to calculate the battery heat generation rate under ultra-fast charging tests and a road trip test, which are further adopted as the inputs to the thermal models. The simulation of the 5C ultra-fast charging test gives the peak temperature rise just 0.47⁰C lower than the experimental measurement, it indicates that the FEA thermal models can provide an accurate temperature prediction of the battery module. / Thesis / Master of Applied Science (MASc) / With a demanding market of electric vehicles, battery technologies have grown rapidly in recent years. Among all the battery research topics, the development of ultra-fast charging, that can fully charge the battery pack within 15 minutes, is the most promising direction to address the range anxiety and improve the social acceptance of electric vehicles. Nevertheless, the application of ultra-fast charging has many challenges. In particular, an efficient thermal management system is significant to guarantee the safety and prolong the service life of the battery pack. This thesis contributes to study the fundamentals of the battery field, and design liquid cooling systems to observe the thermal behavior of a battery prototype module under fast charging and general use. FEA thermal modeling of the battery module is developed to provide a guide for further test validation.
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Computational Methods for the Analysis of Non-Contact Creep DeformationYe, Xiao 01 January 2012 (has links) (PDF)
Currently, various needs from industry, science and national defense strategy demand materials with cutting-edge ultra-high temperature performances. Typical applications of ultra-high temperature materials (UHTMs) are supersonic airplanes, gas turbines and rocket nozzles which usually require continuous service of critical components at temperatures higher than 1600°C. Creep resistance is a critical criterion in designing materials for these applications. Traditional creep characterization methods, however, due to limitations on cost, accuracy and most importantly temperature capability, gradually emerge as a bottleneck.
Since 2004, a group of researchers in the University of Massachusetts, Amherst have been designing a new high temperature characterization scheme that can break through the limits of traditional methods. Their method is based on non-contact creep tests conducted with Electrostatic levitation (ESL) facilities in NASA Marshall Space Flight Center in Huntsville Alabama. The tested sample is levitated in electric field and is heated as well as rotated with specially positioned laser beam. After certain amount of time, the sample deforms under centripetal forces. By comparison of the shape of the deformed sample with results from finite element simulation, creep behavior of the tested material can be characterized.
Based on the same theory, this thesis presents a computational creep characterization method based on non-contact method. A finite element model was built to simulate non-contact creep behavior and results were compared to ESL experiments to determine the creep characteristic. This method was validated both theoretically and numerically and then applied to creep characterization of a promising ultra-high temperature composite from General electric (GE).
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Structural sizing of post-buckled thermally stressed stiffened panelsArsalane, Walid 13 May 2022 (has links) (PDF)
Design of thermoelastic structures can be highly counterintuitive due to design-dependent loading and impact of geometric nonlinearity on the structural response. Thermal loading generates in-plane stresses in a restrained panel, but the presence of geometric nonlinearity creates an extension-bending coupling that results in considerable transverse displacement and variation in stiffness characteristics, and these affects are enhanced in post-bucking regimes. Herein a methodology for structural sizing of thermally stressed post-buckled stiffened panels is proposed and applied for optimization of the blade and hat stiffeners using a gradient-based optimizer. The stiffened panels are subjected to uniform thermal loading and optimized for minimum mass while satisfying stress and stability constraints. The stress constraints are used to avoid yielding of the structure, whereas the stability constraints are used to ensure static stability. Corrugation of the hat stiffeners is also studied through variation of its magnitude and position. A continuation solver has been validated to tackle the highly nonlinear nature of the thermoelastic problem, and formulations for the stability constraints have been derived and imposed to satisfy the static stability of the structure. The study confirms that geometric nonlinearity is an important aspect of sizing optimization and is needed for an accurate modeling of the structural behavior. The results also show that modeling of geometric nonlinearity adds extra complexity to the thermoelastic problem and requires a path-tracking solver. Finally, this work supports that corrugation enhances the stability features of the panel but requires a blending function to reduce stresses at the panel boundaries.
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Structural Analysis and Finite Element Modeling of Aluminum Honeycomb Sandwich StructuresDoukoure, Maimouna 05 1900 (has links)
The objective of this research is to determine how the sandwich's physical characteristics have an impact on the mechanical properties, determine under what conditions the specimens will be lighter and mechanically stronger, and determine if the use of an aluminum honeycomb sandwich as a construction material is feasible. The research has aimed at the use of aluminum sandwiches as light and strong material. The study of the structural layers' damage resistance and tolerance demonstrated that the top and bottom layers play a crucial role. The thesis presents three test results from aluminum honeycomb sandwich compression horizontal, compressive vertical, and bending tests. Also, each group was displayed mechanically and simulated in Abaqus. The study determines the mechanical properties such as maximum elastic stress-strain, ultimate stress-strain, fracture point, density, poison ration, young modulus, and maximum deflection was determined. The energy absorbed by the FEA, such modulus of elasticity, resilience, and toughness, the crack propagation, the test's view shows aluminum honeycomb behaved like a brittle material with both compression test. And the maximum deflection, crack propagation, shear forces, bending moment, and images illustrated that the layers play a crucial role in the 3-point bend test.
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Design and Modeling Environment for Nano-Electro-Mechanical Switch (NEMS) Digital SystemsHan, Sijing 08 March 2013 (has links)
No description available.
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Non-Destructive Investigation & FEA Correlation on an Aircraft Sandwich Composite STructureBail, Justin January 2007 (has links)
No description available.
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