Thermal barrier coatings (TBCs) have been used widely in aerospace and land-based gas turbines. The TBC system consists of a top coat layer, a thermally grown oxide (TGO), a bond coat layer and a substrate. The growth kinetics of the TGO significantly affects the durability of TBCs. At a critical TGO thickness, the growth stresses exceed the ceramic-bond coat interface strength, resulting in TBC system failure. Regardless of the deposition method used, it is vitally important to accurately predict the TBC lifetime by investigating the determinants of the failure. The main objective of this study was to investigate the effect of oxidation stress induced by TGO layer in high temperature cycling environment through a series of reliable numerical simulations. Indeed, this oxidation stress is a known factor of interface degradation, and may result in failure of the ceramic-metal interface. A 2-D finite element model of the TBC was built via ANSYS APDL software, to conduct parametric studies of increasing complexity. The model accounted for elasticity first, before creep was integrated. Then, the model included swelling induced by phase transformation associated with oxidation, incorporating the effect of volumetric expansion of the newly grown TGO. This coupled oxidation constitutive approach was implemented for a typical air plasma spray deposited TBC coating. The interfacial radial stresses induced by the gradual oxidation were investigated. Different morphologies of the TBC interface were also considered to analyze the roughness effect on interface stresses. A complete model including swelling, creep, aging effects on the TBC layers at a given roughness was finally investigated.

The detection of internal log defects has been shown to have a potential for increasing the lumber value. As an alternative to other available expensive log scanning devices, a method using radio frequency waves has been used to detect the knots. The main focus of the current research is to investigate the effectiveness of using radio frequency waves to detect the knots. Electrostatic finite element analysis is performed to predict the defects in logs. A script has been written using the commercial finite element ANSYS software to predict defects in log sections. The results are then compared with the experimental data measured on actual log sections. Analysis proved that it is possible to detect presence of knots in the log sections.

Im Vortrag wird das Vorgehen zur Konstruktionsoptimierung mittels parametrischer FE-Simulation beschrieben. Die einzelnen Schritte werden dargestellt und am Beispiel eines Übertragungselements für Klauenkupplungen erläutert. Zunächst wird der Optimierungsgegenstand vorgestellt und die Festlegung der Entwurfsvariablen und Zielfunktionen beschrieben. Im Anschluss werden die Erstellung des FE-Modells und die Durchführung der Optimierungsrechnung schrittweise erläutert. Abschließend folgen ein Vergleich verschiedener Optimierungsmethoden und die Zusammenfassung. Als Software wurden ANSYS und Autodesk Inventor verwendet.

Ingeniera Civil Mecánica / En esta memoria se estudia el comportamiento del relave de cobre chileno con diferentes concentraciones, específicamente con concentraciones en peso de 35% 45%, 50% y 55%. Es importante realizar este estudio debido a la necesidad del país de recuperar las aguas de tratamiento de los relaves, por la escasez de agua en el norte de Chile, aumentando la concentración de la pulpa. El principal objetivo de esta memoria es modelar el relave asumiendo un comportamiento como fluido no- newtoniano, estudiando la reología de éste y ver los efectos que tiene en cajones de transición Para esto se realizarán simulaciones en el software ANSYS Fluent 14.5, donde primero se hace una recopilación de los antecedentes más importantes para poder caracterizar el relave y el fluir de este en canaletas y cajones, tanto para fluidos newtonianos, como no-newtonianos. También se estudia la reología del relave para las diferentes concentraciones, utilizando correlaciones obtenidas de antecedentes. Luego se crea un diseño hidráulico del cajón de transición para luego generar un mallado, y a través de condiciones de borde adecuadas, lograr simular el fluir del relave con las concentraciones antes mencionadas. El análisis es transiente de 30 seg. de simulación. Se realizan dos simulaciones del relave con concentración en peso 35% una con un modelo de flujo turbulento k-e y otro con un modelo viscoso laminar. Luego se procede a realizar las simulaciones del relave de alta concentración en peso como plástico de Bingham. Dentro de los resultados más importantes se logra validar los resultados obtenidos, comparando las velocidades numéricas con las teóricas. Además, haciendo una comparación entre el modelo laminar y turbulento, se justifica el uso del modelo viscoso laminar para la simulación del fluir del relave. Por último, dado los resultados obtenidos de sedimentación y desgaste del cajón, se puede seleccionar la geometría diseñada como la adecuada, dadas las condiciones de operación planteadas en la memoria.

In 2009, WPI formed a Presidential Task Force to engage the WPI community in sustainability research, thought, and action. One of the Presidential Task Force's specific objectives is to improve campus environmental performance, which includes energy conservation. Several new buildings such as the Bartlett Center and East Hall have utilized new green building techniques and materials. Older buildings at WPI which were built before new green building techniques and materials were developed can be equipped with photovoltaic systems to reduce the environmental impact and increase clean energy use. This thesis presents a rooftop photovoltaic array design for the George C. Gordon library at WPI which is expected to produce over 27,000 kWh and offset over 56,000 lbs of carbon dioxide emissions annually. The materials science and engineering of the photovoltaic system components are an important part of the design process. Structural and thermal modeling of photovoltaic components during the initial phase of array design is critical to the success of the PV system and maximizing the energy from the system. This thesis presents how differences in photovoltaic materials and mounting systems result in changes in lifetime and reliability. Using common wind, ice, snow and hail loads for the Worcester, MA area ANSYSâ„¢ structural simulations show that an attached mounting system is more structurally stable than a ballasted system. Using local weather data and thermal cycling, ANSYSâ„¢ thermal simulations show that silicon PV modules outperform other technologies at lower temperatures while cadmium telluride PV modules outperform other technologies at higher temperatures. It is recommended that WPI install poly-silicon PV modules, such as Evergreen Solar PV modules, to maximize power output.

<p>The world we are living in today is pushing the technology harder and harder. The products need to get better and today they also need to be friendlier to the environment. To get better products we need better analysis tools to optimize them and to get closer to the limit what the material can withstand. Siemens industrial Turbomachinery AB, at which thesis work is made, is constructing gas and steam turbines. Gas and steam turbines are important in producing power and electricity. Electricity is our most important invention we have and most of the people are just taking electricity for granted. One way to produce electricity is to use a gas turbine which is connected to a generator and by combing the turbine with a steam turbine the efficiency can be up to 60 %. That is not good enough and everybody want to get better efficiency for the turbines, meaning less fuel consumption and less impact on the environment.</p><p>The purpose of this thesis work is to analyze a tool for rotor dynamics calculations. Rotor dynamics is important in designing a gas turbine rotor because bad dynamics can easily lead to disaster. Ansys Classic version 11 is the analyze program that is going to be evaluated for the rotor dynamic applications. Nowadays rotor dynamics is done with beam elements i.e. 1D models, but in this thesis work the beam elementsare going to be changed to solid elements. With solid elements a 3D model can be built and thanks to that more complex calculations and simulations can be made. For example, with a 3D model 3D effects can be shown and e.g. simulations with blade loss can be done. 3D effects are not any problem today but in the future the gas turbines have to get better and maybe also the rotational speed will increase.</p><p>Ansys isn’t working perfectly yet, there are some problems. However Ansys have a good potential to be an additional tool for calculations of rotor dynamics, because more complex calculations and simulations can be done. More knowledge and time needs to form the rules to modeled a rotor and developing the analysis methods. Today the calculated lateral critical speeds are lower than the ones obtained from the in-house program Ardas version 2.9.3 which is used in Siemens Industrial Turbomachinery AB today. The difference between the programs are not so big for the four first lateral modes, only 3-8 %, but the next three lateral modes have a difference of 10-20 %. The torsion frequencies from Ansys are the same as the ones from Ardas, when the Solid186 elements are used to model the blades.</p>

Among the MEMS field, the design and simulation of piezoelectric micro-actuators are difficult as compared to thermal micro-actuators and electrostatic micro-actuators. The main reason of the piezo-electric material coupling effect is difficult to calculate. However the piezo-electric material has several advantages and characteristics for designing micro-actuators. Moreover, the design is usually done by the experimental or try-and-error method which is not so effective. It should be noted that there is not a simple method already developed for the design and simulation of the piezo-electric micro-actuators. In this research we proposed to use the software of ANSYS for the simulation of piezo-electric micro-pump. Simulation of force output of piezo-micro-pump can use ANSYS software to establish the simulation system of piezo-micro-pump. The micro-pump will have different resonance frequency, back-pressure and fluid due to piezo-electric characteristic. In this study, the author used a square, rectangle and circle geometric shape to simulate the result, each geometric shape has four different kinds of size. As a result, there are twelve groups of different simulation results. We are able to using the chart to present and explain the relation between resonance frequency and displacement.

The thesis is part of IBCleaning and Robotdalen project "Automated Ice-blasting" are based on blasting walls on the inside of cargo containers with dry ice using an industrial robot and therefore clean the surface. To insert the industrial robot in the dirty container a specially designed rail system has been developed.This thesis aims to analyze and calculate the strength parameters of the assembly consisting of the robot and the specially designed rail system. One more task is to examine whether there is an opportunity to contribute to an improvement proposal. The report describes briefly Ice Blasting and how the automation of this can be designed. Literature Studies in solid mechanics and tutoring in ANSYS has been performed in parallel with the work and used to compare, evaluate and resolve the various situations that occur in the construction. FEM analysis using “ANSYS program” has been implemented to support the calculations and analysis realized. ANSYS was also used when it was not possible to perform a manual calculation due to the complicated procedures or multiple operations simultaneously.I spent some of the time to realize 3D-drawings using ”Pro-Engineer program”, drawings that have been sent on to ANSYS to perform various tests on the design and obtain concrete results.The calculations are performed based partly on information from the company and partly on reasonable assumptions in order to supplement missing data in the spreadsheet calculations.

The detection of corrosion in pipes is of major importance to the oil and chemical industries. Current methods involving point-by-point inspection are available for the detection of general wall loss associated with corrosion, but unfortunately the current methods tend to be very slow, limited to single positions, thus make the inspection of the kilometers of pipeline typically found in industrial plants virtually impossible. Ultrasonic guided waves provide an attractive solution to this problem because they can be excited at one location on the pipe and will propagate many meters along the pipe, returning echoes indicating the presence of corrosion or other pipe features. Nevertheless such techniques still have many practical difficulties in application due to the complex characteristics of guided waves such as dispersion and mode conversion. This thesis studies guided waves influenced by the welded supports, a.k.a. pipe shoe. A research of the reflection of mode-converted guided waves from pipe shoes on pipes in the frequency range 18-32 kHz has been carried out. Measurements are made on a 6 inch bore diameter, 7.1mm wall thickness pipe. The axisymmetric symmetric T(0,1) mode is incident on the pipe shoes and the mode-converted guided waves are received in reflection. In parallel, a finite element model is used to simulate the experiments by using Ansys. Received signals are separated into single-mode with a mode extraction technique. This research reveals that when T(0,1) propagates through the pipe shoe, the energy of T(0,1) passes into the pipe shoe. The leakage phenomenon results in the complexity and misinterpretation of the echo.

ASCE Manual No.74 (2010) and the Electric Power Research Institute (EPRI, 1997) provide methods for calculating the unbalanced longitudinal loads on a transmission line due to a wire breakage. The calculated loads from the two are different. In this study, a simplified transmission line was created using the equivalent geometric properties of a detailed transmission line. Non-linear dynamic analyses of the 10-span simplified transmission line due to cable breakage events in the first span were studied using ANSYS. The analyzed longitudinal loads were found to vary for different S/S, S/I, and K’s as specified in the EPRI. An equation for the longitudinal load factor as a function of the S/S, S/I, and K was then formulated based on the analysis. The longitudinal load factors from the formulated equation were found to be almost double those given by the ASCE manual and comparable to those calculated using the EPRI formulation.