Engineering Commons^™

Computational Modelling Of Resin Infiltration And Curing In High Pressure Resin Transfer Molding, Anthony Paul Rexford Sherratt

Electronic Thesis and Dissertation Repository

Increased pressure on automotive manufactures to reduce overall greenhouse gas emissions from their vehicles has driven research into replacing conventional steel components with carbon fiber reinforced plastics (CFRP). This is due to their high weight specific properties and design freedom. High pressure resin transfer molding (HP-RTM), a derivative of resin transfer molding, is a manufacturing process for CFRP’s that offers high automation potential and low cycle times; critical properties of a manufacturing process for the automotive sector.

The goal of the present work is to increase the accuracy and reduce the computational overhead of current RTM infiltration and curing models. …

A Computational Fluid Dynamics-Based Surrogate Wind Turbine Blade Aerodynamic Model For Hybrid Simulation, Eric Lalonde

Electronic Thesis and Dissertation Repository

Hybrid simulation (HS) is a promising technique for studying wind turbines due to the presence of scaling errors in wind tunnel testing. However, HS of wind-loaded structures is limited by the current practice of using lower-accuracy, "pre-calculated" aerodynamic loads, which uncouple the aerodynamic loading from the structural response. This thesis presents six stand-alone studies that collectively build towards a novel HS framework that employs a computational fluid dynamics (CFD) based surrogate model to generate higher-accuracy aerodynamic loads within the HS loop. An experimentally-validated residential wind turbine model equipped with an external damping system was used to illustrate the proposed framework. …

Integrated Modelling Of Wastewater Treatment And Sewer Processes - Interactions Of Fluid Flow, Mass Transfer, And Biochemical Reactions, Ahmed Khalil

Electronic Thesis and Dissertation Repository

Numerical modelling of wastewater management systems is crucial for investigating alternative designs and developing strategies for operation and control that improve the performance of the treatment stage (such as improving the aeration systems in activated sludge systems). Modelling can also help operators to mitigate common problems that arise from unwanted biochemical conversions in the sewer networks (such as the production of sulfide and methane). Therefore, this work focuses on two major areas related to modelling wastewater management systems. First, it seeks to develop more accurate models for aeration systems in activated sludge reactors. Second, it seeks to study the mathematical …

Analytical And Computational Modelling Of The Ranque-Hilsch Vortex Tube, Nolan J. Dyck

Electronic Thesis and Dissertation Repository

The Ranque-Hilsch vortex tube (RHVT) is a simple mechanical device with no moving parts capable of separating a supply of compressed fluid into hot and cold streams through a process called temperature separation. The overall aim is to develop models which can be used to assess the temperature separation mechanisms in the RHVT, leading to a better overall understanding of the underlying physics. The introductory chapter contains a thermodynamic analysis and introduction to the flow physics, alongside three miniature literature reviews and critiques identifying research gaps.

The body of the thesis contains three articles. The first article studies the flow …

Identification Of Aerodynamic Damping For Flexible Structures Using Wind-Induced Response, Shea Laventure

Electronic Thesis and Dissertation Repository

Damping estimation is a critical task to perform during the design of slender structures, or for existing structures. This is to ensure the response of the structure is within allowable limits and to determine if additional damping is necessary from auxiliary devices. If a slender structure is experiencing wind loading, a phenomenon known as aerodynamic damping arises, which has the potential to reduce the damping of the structure. The most efficient method to estimate aerodynamic damping is to use a system identification technique, which requires only the input forces and output response of the structure. This thesis describes how to …

Disinfection And Advanced Oxidation Of Highly Absorbing Fluids By Uv/Vuv Light: Process Modeling And Validation, Ferdinando Crapulli

Electronic Thesis and Dissertation Repository

One of the limitations in treating highly absorbing fluids with ultraviolet photoreactors is the short light penetration into the fluid leading to the following issues: (a) if not engineered properly, ultraviolet photoreactors dealing with highly absorbing fluids are likely to be energy-inefficient due to a non-ideal use of emitted photons and non-uniform dose distribution (b) the quantification of photo-chemical rate constants could be a challenging task due to the severe mixing-limited conditions of the experimental apparatus used during the investigation. As a result, new lab-scale apparatus (alternative to the conventional collimated beam system) and modeling approaches are needed in order …

Numerical Evaluation Of Aerodynamic Roughness Of The Built Environment And Complex Terrain, Daniel S. Abdi

Electronic Thesis and Dissertation Repository

Aerodynamic drag in the atmospheric boundary layer (ABL) is affected by the structure and density of obstacles (surface roughness) and nature of the terrain (topography). In building codes and standards, average roughness is usually determined somewhat subjectively by examination of aerial photographs. For detailed wind mapping, boundary layer wind tunnel (BLWT) testing is usually recommended. This may not be cost effective for many projects, in which case numerical studies become good alternatives. This thesis examines Computational Fluid Dynamics (CFD) for evaluation of aerodynamic roughness of the built environment and complex terrain.

The present study started from development of an in-house …

Numerical Investigation Of Highly Curved Turbulent Flows In Centrifugal Compressors And In A Simplified Geometry, Kevin J. Elliott

Electronic Thesis and Dissertation Repository

Curvature effects are investigated in terms of a recently developed curvature corrected turbulence model in turbomachinery applications. Two centrifugal compressor stages and a curved geometry modelled after a centrifugal impeller are simulated using the curvature corrected SST (SST-CC) turbulence model. This work improves the understanding of how the SST-CC model predicts curvature effects. An analysis of the SST-CC production multiplier in both centrifugal cases reveals that the model is appropriately accounting for curvature effects, showing increased production near concave surfaces and decreased production near convex surfaces. This correlates well with the simplified geometry results and demonstrates that the simplified geometry …