Connecting rod are found in most combustion engines and transmits thrust from the piston to the crankshaft. The connecting rod needs to withstand forces from the piston and inertia forces which results in axial tension, compression stresses and bending. Today the most common manufacturing techniques in automotive industry are drop-forging, die-casting and the Powder Metallurgy technique used is powder-forging. In this Master Thesis different connecting rod designs for a single press PM manufacturing process were created and evaluated as a part of Höganäs AB's Total Powder Metal Car project, TPMC. This paper will serve as a basis for future connecting rod projects at Höganäs AB when choosing a suitable connecting rod design. The main objective of this Master Thesis is to evaluate different designs in regards to the following: Buckling strength Fatigue life Manufacturing rating The study shows that there is evidence that a single pressed connecting rod is possible. No absolute answer of which design is the best is given in this paper since in depends on different parameters and application. For each parameter examined there are results presented and arguments for and against each design which can aid designers in future work. Suggestions of improvement on both the method and on the designs are presented in respect to the results. The improvements may potentially increase the fatigue life, buckling strength and improve manufacturability.

Esta pesquisa pretende verificar as características da análise do ambiente organizacional – parte integrante dos principais métodos de planejamento estratégico, ou seja, a verificação das ameaças e oportunidades - em termos de grau de formalização, nível de participação, mecanismos e fontes de consulta - efetuada no planejamento estratégico das empresas que exportam software e serviços correlatos. Pretende ainda verificar o quanto o ambiente organizacional interferiu ao longo da execução dos projetos derivados das decisões estratégicas de exportação, e quais respostas foram dadas pelas empresas às mudanças das condições ambientais. O período de análise portanto vai desde a concepção do projeto até que a exportação esteja em curso. A amostra intencional foi retirada da lista de empresas exportadoras consideradas casos de sucesso pelo Instituto de Tecnologia de Software – ITS, órgão que tem como missão promover a melhoria do software nacional. As empresas tiveram seus estágios de internacionalização e suas estratégias analisadas e classificadas. O trabalho encerra-se com considerações sobre a influência do ambiente organizacional nos projetos estratégicos de exportação de software, apontando a quais segmentos ambientais esse tipo de empresa é mais sensível, e tecendo um perfil da amostra, enfatizando o alto grau de empreendedorismo e a boa rede de relacionamentos, característica comum a todas empresas investigadas. / This research intends to verify the characteristics of organizational environmental analysis, the check point of threats and opportunities – part of the main strategic planning methods, in terms of grade of formalization, participation level, mechanisms and information sources, applied to the strategic planning process to Brazilian companies that export software and correlative services. Intends to check if and how much the organizational environment interfered during the execution of the projects derivates from strategic decision of exportation, and what kind of answers was given by the companies to the environmental condition changes. The analysis period begins on the conception of the project and goes up the company to reach the international market. The intentional sample was get from the list of the exporters companies considered success cases by the Instituto de Tecnologia de Software – ITS, organ with the mission to promote the Brazilian software improvement. The companies had theirs internationalization stages and strategies analyzed and classifieds. The work finishes with some considerations about the influence of the organizational environmental in the strategic projects of software exportation, pointing out for what environmental segments the companies more sensitive, and plotting the profile of the sample, emphasizing their high grade of entrepreneurship and the good relationship network, common characteristic of all investigated companies.

Commercial composite aerospace structure is required to be designed and managed under the damage tolerant principle. Airworthiness is maintained through a process of regulated inspections and if required maintenance. Currently inspections use visual and assisted visual (non-destructive inspection - NDI) techniques. Damage tolerant operation is therefore reliant on inspectability. Unlike metal structure composite and adhesively bonded structure may show few if any recognisable indicators prior to rapid failure, either visually or using NDI. Although stringent manufacturing processes are demanded to best ensure components are fit for service strategies such as reducing stresses by oversizing components or in the case of bonded features additional mechanical fasteners may be included to allow operation with this potential structural uncertainty. Structural Heath Monitoring (SHM) uses data from in-situ sensors to assess the condition of the structure. If via SHM any uncertainty associated with difficult to inspect components could be eliminated less reliance would be required of additional structure or features allowing lighter and more efficient structure to be viable with no impact on current airworthiness demands. Despite much previous research no SHM system is in use with in-service composite or bonded aerospace components. When operating a structure under Damage-tolerance operational requirements damage must be positively identified to allow repairs to be made whist ensuring appropriate airworthiness demands are maintained. Such demands must also be met by structure inspected using SHM. Unlike previous studies this research combines the process of structural design and in-situ monitoring to address the issues identified. Termed SHM enabled design this approach allows the implementation of monitoring technology and the potential for benefits including the reduced reliance on inefficient additional structure to be viably included in actual structure ... [cont.].

Assessment of concrete buttress dams today consists of using analytical methods to investigate the stability in different failure modes. However, they simplify the problem at hand and neglect certain important features linked to geometry and thus not truthfully appraise the structures real stability.  This could be economically costly in assessments of both existing dam structures as this would eventually lead to unwarranted rehabilitation. The same can be said for dams under design.   Kalhovd dam is a concrete buttress dam that has recently undergone assessment where certain sections proved unstable in either failure mode. This study focused specifically on a buttress, numbered 49, of said dam which was deemed in the assessment to be unstable in the overturning and sliding failure mode.   The methodology used was to assess and compare stability for different methods of calculation, meaning analytical versus numerical analysis. The numerical analysis was performed with two-dimensional finite element analyses in a commercial FEM-software called ATENA which focuses on reinforced concrete structures. The numerical models made, were then probabilistically analysed by randomizing various material parameters to see their effect on stability. Some FEA models discarded the conventional way of modelling loads, as required by standards, to more realistically portray load actions on dams based on historical measurement.   Results from this study showed dissimilarity of stability for buttress 49 depending on which method of analysis was performed. Analytical methods proved to yield the most conservative results and concluded the structure unsafe, while including an accurate representation of the geometry in FEA models improved the stability such that it can be considered stable against load actions stated in guidelines.   Furthermore, material parameters randomized in the probabilistic analysis substantiated that various concrete variables had relatively little effect on structural overall strength in the most common failure modes.

This thesis presents a stable fluid structural interaction technique to simulate the dynamics of tissue valves including bio-prosthetic heart valves and natural heart valves under physiological Reynolds numbers. A partitioned approach is implemented where the equations governing the flow and the displacement of the structure are solved using two distinct solvers. A FEAP based solid solver is strongly coupled to the p-ELAFINT flow solver using subiteration procedure. The flow solver has been massively parallelized so that the domain can be distributed among several processors. The fixed Cartesian method with adaptive mesh refinement in p-ELAFINT enables us to perform fast and efficient flow computations of problem involving moving boundaries such as heart valve leaflets. To capture the structure deformation, Enhanced Assumed Solid shell element has been implemented into the solid solver which is known for its locking free and superior bending characteristics. Aitken Relaxation method which dynamically computes the relaxation parameter is used for relaxing the solid displacement in the FSI coupling. This helps the subiteration procedure to achieve a faster convergence compared to traditional Subiterative procedures with fixed relaxation parameter. Fung type material model with experimentally derived parameters is used as the constitutive model to capture the realistic solid deformation. Opening phase of a bicuspid aortic valve (BAV) model derived from a patient specific data and a pericardial bioprosthetic valve model were simulated using the FSI algorithm with realistic material parameters under physiological flow conditions. It was observed that the valves attained its fully open position under 35 milliseconds which is similar to the physiological opening. The bioprosthetic valve attained a fully circular orifice while the BAV attained an ellipsoidal shaped orifice at its fully open position. In the BAV, strong vortical patterns were observed at peak systole and recirculation zones were observed near the sino-tubular junction. The work presented in this thesis be seen as a platform from which complex patient specific data can be modeled under physiological conditions and as a base to include contact mechanics with which complete cardiac cycle can be simulated.

This dissertation aims to advance the field of structural optimization by creating and demonstrating new methodologies for the explicit inclusion of manufacturing issues. The case of composite aerospace structures was a main focus of this work as that field provides some of the greatest complexities in manufacturing yet also provides the greatest incentives to optimize structural performance. Firstly, the possibilities for modifying existing FEA based structural optimization methods to better capture manufacturing constraints are investigated. Examples of brick-based topology optimization, shell-based topology optimization, parametric sizing optimization and manufacturing process optimization are given. From these examples, a number of fundamental limitations to these methods were observed and are discussed. The key limitation that was uncovered related to a dichotomy between analytical methods (such as FEA) and CAD-type methods. Based on these observations, a new Knowledge-Based framework for structural optimization was suggested whereby manufacturing issues are integrally linked to the more conventional structural issues. A prototype system to implement this new framework was developed and is discussed. Finally, the validity of the framework was demonstrated by application to a generic composite rib design problem.

<p>This Master’s thesis is summery of a comparative study of 2 commercial CAD-integrated</p><p>FE-programs. These FE-programs were CATIA v5 and ABAQUS 6.3-7. The primary</p><p>objective of this study is to investigate the basic FEA capabilities of CATIA and</p><p>ABAQUS 6.7-3 in performing the linear static analysis and to identify whether there are</p><p>any differences and similarities between results the both Finite Element FE codes give.</p><p>The overall research question in the present thesis is: Do different FE programs, here</p><p>CATIA and ABAQUS, give the same results for FE analysis giving the same models if</p><p>subjected to the same boundary conditions? This research seeks to achieve its aims</p><p>through making a comparative qualitative study. Certain pre-selections were performed in</p><p>advance of conducting Finite element analysis and the comparison process to ensure that</p><p>results would reflect only the most relevant and meaningful differences and similarities</p><p>between the both FE-codes. Five different 3D solid models have been selected to perform</p><p>linear static Finite element analysis on. All these models (case studies) are created in</p><p>CATIA V5 and the linear static analysis conducted on using FE-codes CATIA v5 and</p><p>ABAQUS 6.7-3. Three static responses (results) of the linear static analysis have been</p><p>adopted as criteria for comparisons purposes. These criteria were: (1) displacements, (2)</p><p>Von Mises stress, and (3) principal stress. The results of comparisons showed that there is</p><p>a very good agreement in most cases and small gap between in a few cases. Results of</p><p>this study demonstrate that the both FE-programs CATIA v5 and ABAQUS 6.7-3 have</p><p>good capabilities to perform FE-analysis and they give very near results. Reason behind</p><p>differences is that each of them uses a different algorithm for solving problems. The final</p><p>answer for the research question is given with valuable recommendations for future work</p><p>in the scope of this research.</p>

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Due to the environmental issues related with fuel consumption and additionally passenger safety, aluminum space frame chassis is promising a big opportunity to design a lightweight structure with a high stiffness. Despite the lower stiffness and strength of aluminum in comparison to the conventional steel chassis, it can be compensated with changing thickness and design of structure by space frame geometry In this study, instead of using steel for automobile chassis, main goal is producing a space frame structure with using aluminum in an extrusion and sand casting processes and improve the stiffness. Chassis is designed according to calculations for moment of inertia, torsional and bending stiffness and in sufficient structural stiffness which can compete with steel chassis. Static finite element analysis was carried out to understand the chassis bending, torsional stiffness and fatigue behaviors. For frontal collisions, dynamic finite element analysis was also done to determine increases in the energy absorbance, specific energy absorbance and peak force for passenger safety. Aluminum profiles were produced by hot extrusion and joined with sand casting parts by TIG welding to manufacture a space frame structure. For main chassis profile, 6063 series of aluminum alloy was selected due to availability for extrusion process, weldability and having sufficient tensile strength and percent elongation and treatment response. Three point bending test was carried out to determine flexural strength. Moment of inertia calculations were done. Some parts such as side frame and shock absorber tower were produced by sand casting method. A similar composition to Silafont &ndash / 36 aluminum alloy was selected because of its high fluidity and good mechanical properties / despite it is a die cast alloy. Tensile, hardness and Charpy impact test were conducted to determine the mechanical characteristics of Silafont - 36 sand cast alloy. In addition to microstructure features and thermal analysis were also carried out to achieve sufficient alloy properties. Heat affected z one was investigated by hardness and tensile test to determine the mechanical properties change after welding process. In this space frame development study, A, B and C pillar parts were produced by Al &ndash / Si sand casting and T6 heat treatment then welded together by TIG welding and finally assembled on the bottom chassis frame produced by using 6063 extrudes welded by 4000 series electrodes. The space frame chassis was studied by also computer simulation to test and see critical points which must be modified during manufacturing. Besides the experimental and theoretical studies, space frame was also produced at the same time. According to the experimental results, the feasibility of the production of lightweight and solid chassis structure was achieved.

Characterizing hidden solder joint shapes is essential for electronics reliability. Active thermography is a methodology to identify hidden defects inside an object by means of surface abnormal thermal response after applying a heat flux. This research focused on understanding, modeling, and predicting hidden solder joint shapes. An experimental model based on active thermography was used to understand how the solder joint shapes affect the surface thermal response (grand average cooling rate or GACR) of electronic multi cover PCB assemblies. Next, a numerical model simulated the active thermography technique, investigated technique limitations and extended technique applicability to characterize hidden solder joint shapes. Finally, a prediction model determined the optimum active thermography conditions to achieve an adequate hidden solder joint shape characterization. The experimental model determined that solder joint shape plays a higher role for visible than for hidden solder joints in the GACR; however, a MANOVA analysis proved that hidden solder joint shapes are significantly different when describe by the GACR. An artificial neural networks classifier proved that the distances between experimental solder joint shapes GACR must be larger than 0.12 to achieve 85% of accuracy classifying. The numerical model achieved minimum agreements of 95.27% and 86.64%, with the experimental temperatures and GACRs at the center of the PCB assembly top cover, respectively. The parametric analysis proved that solder joint shape discriminability is directly proportional to heat flux, but inversely proportional to covers number and heating time. In addition, the parametric analysis determined that active thermography is limited to five covers to discriminate among hidden solder joint shapes. A prediction model was developed based on the parametric numerical data to determine the appropriate amount of energy to discriminate among solder joint shapes for up to five covers. The degree of agreement between the prediction model and the experimental model was determined to be within a 90.6% for one and two covers. The prediction model is limited to only three solder joints, but these research principles can be applied to generate more realistic prediction models for large scale electronic assemblies like ball grid array assemblies having as much as 600 solder joints.