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- Resource Type:
- Thesis
- Creator:
- von Zuben, Elizabeth Lynn
- Abstract:
- As identified in the 2021 IPCC AR6 WGIII report, wind energy has a high potential to reduce greenhouse gas emissions. The deployment of wind energy, however, has fallen behind its potential in part because of the need for improved wind power predictions. This thesis combines historical power production data, meteorological station data, reanalysis data, and numerical weather prediction output data (WRF model) to determine the optimal combination of data sources and variables for wind power prediction using a random forests model. A study then further evaluates reanalysis data and methods of bias correction for this type of data, to improve power predictions at 52 wind farms across Canada using power curve and machine learning methods. Recommendations are proposed for: the use of data sources and important input variables; the utility of global reanalysis data sources by terrain features; and the utility of bias correction methods for downstream wind power prediction.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Engineering, Mechanical
- Date Created:
- 2022
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- Resource Type:
- Thesis
- Creator:
- Robertson, Taylor
- Abstract:
- A novel ceramic matrix composite (CMC) system consisting of a commercially available SiC fibre, variations of electrophoretically deposited (EPD) fibre-matrix interphases, and a liquid metal melt infiltrated matrix was designed and characterised. A factorial design of experiments approach was undertaken to evaluate the deposition variables which would result in a functioning fibre-matrix interphase. A 25-2 partial factorial design matrix was selected with factors: electric potential, deposition time, surfactant, binder, and solids loading. The design matrix was replicated for four different EPD fibre-matrix interphase coating combinations: Al2O3/SiC, BN/PSZ, ZrC/ZTA, and SiC/Si3N4/SiC. Microcomposites were evaluated for tensile properties using a standard displacement controlled tensile test program. Microcomposites were tested at room temperature immediately following fabrication and following exposure to a standard atmosphere at 1000 °C for 1 h. Samples with ZrC/ZTA and SiC/Si3N4/SiC coatings demonstrated the best tensile properties in room temperature tests while samples with BN/PSZ and SiC/Si3N4/SiC coatings demonstrated the best retention of tensile properties following high temperature exposure. Subsequent SEM analysis revealed that coatings with smaller particle diameters as the inner layer of the fibre-matrix interphase coating produced more uniform coatings and the less fibre degradation due to oxidation following high temperature exposure. Additional microcomposites were fabricated for high temperature tensile testing; however, these samples were unable to bear recordable loads, an SEM examination revealed significant degradation of the matrix phase beneath the high temperature adhesive. Optical microscopy was used to evaluate coating thicknesses of coated fibre bundles prior to heat treatments. Measured coating thickness indicated that generally higher deposition times resulted in thicker coatings; however, coatings produced using 25 V electric potential were thicker than coatings produced using 12.5 V and 50 V electric potentials. This is likely due to a greater deposition efficiency factor at 25 V. FEA analysis was used to evaluate the electrical properties of an idealized version of the stationary EPD cell. This analysis showed a significant variation in the electric field along the fibre axis as well as a significant variation in electrical field between fibres in the centre of the fibre bundle and on the outer edge of the fibre bundle.
- Thesis Degree:
- Doctor of Philosophy (Ph.D.)
- Thesis Degree Discipline:
- Engineering, Mechanical
- Date Created:
- 2022
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- Resource Type:
- Thesis
- Creator:
- Beauchamp, Benjamin
- Abstract:
- This thesis discusses the energy savings, performance, and cost savings of various SAHP typologies in Canada, focusing on parallel systems. Typologies are evaluated for two detached housing archetypes, across a variety of Canadian climates. Modelling takes place in two stages. A first stage using a spreadsheet tool to determine which typology holds the most potential followed by a more detailed second stage in TRNSYS to investigate it. The first stage found that parallel SAHPs hold the most potential. The second stage found that parallel systems provided significant savings across all cities and housing archetypes. A combination of SDHW and ASHP outperformed the parallel system at low collector areas. However, no predicted savings were high enough to payback the predicted installation costs. This document explains the models, assumptions, and results. Recommendations are discussed for future research on system sizing, typologies of interest, heat pump modelling, and component costing.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Engineering, Mechanical
- Date Created:
- 2023
-
- Resource Type:
- Thesis
- Creator:
- Asi, Victoria Usang
- Abstract:
- The wind power industry has experienced fast and tremendous growth, globally, in recent years. Consequently, there is a growing interest in investigating aerodynamics and aeroacoustics characteristics of wind turbines and developing environmental standards aimed at decreasing noise levels in the design and manufacture of these machines. This study was carried out in the Carleton University Wind Induced Dynamic Laboratory (WInDLab) that was designed to evaluate and quantify noise levels emitted by a small horizontal axis wind turbine. This investigation provided the first-ever set of measurements carried out in the WInDLab following the successful installation of the wind turbine. The background acoustic data obtained for the wind tunnel showed that the wind tunnel is not quiet enough for measurements of the type undertaken. The wind tunnel would need to be silenced and acoustically treated to capture noise with low frequencies. Recommendations for further work have been provided.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Sustainable Energy
- Date Created:
- 2023
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- Resource Type:
- Thesis
- Creator:
- Macmillan, Wade Richard
- Abstract:
- The work of this thesis is part of the RoboDeb project, aimed at investigating the application of industrial robots on deburring sheet metal parts. This thesis presents investigations, developments, and implementations of trajectory planning algorithms to automate trajectory design. This thesis first develops custom CAD/CAM software called the Planar Computer Automated Trajectory (PCAT) planning algorithm to establish baseline performance. Trajectory planning is next automated using the novel Planar Image-Space Trajectory (PIST) planning algorithm, which uses computer vision alone to generate machining trajectories. The PIST algorithm is completely automated, with no required CAD data of the workpiece, adapting to new workpieces or manufacturing imperfections. The feasibility of the PIST algorithm is investigated through robotic deburring experimentation, where it successfully deburred the sheet metal parts. The PIST algorithm proved to be the preferred candidate over the PCAT algorithm, as it provided an indistinguishable resulting surface finish while reducing the setup time.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Engineering, Aerospace
- Date Created:
- 2022
-
- Resource Type:
- Thesis
- Creator:
- Brunt, Nicholas Alec
- Abstract:
- This thesis introduces a novel, ambient-temperature district energy system topology that enables bi-directional mass flow to booster heat pumps and includes distributed solar-thermal generation. A detailed model of this system is developed in MATLAB-Simulink, and an equivalent model is developed for a conventional, supply-return district system. The systems are compared—with and without solar-thermal integration—in technical, environmental, and economic analyses. Annual simulations are conducted for the case study: a district energy system in Ottawa with 12 building clusters. The ambient system achieves an annual coefficient of performance of 1.40 without solar and 1.43 with solar. The conventional system achieves annual coefficients of performance of 1.26 and 1.28, respectively. The solar fractions of the ambient and conventional systems are 5.5 and 4.0% for heating and 9.3 and 10.0% for cooling, respectively. The ambient system (without solar) decreased annual carbon emissions by 32.16% relative to the conventional system, a significant improvement.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Sustainable Energy
- Date Created:
- 2023
-
- Resource Type:
- Thesis
- Creator:
- Gzenda, Vaughn Michael
- Abstract:
- This thesis studies geometric formulations of a slow-fast realization of nonholonomic mechanical control systems mediated by strong friction forces. Such realization is motivated by wheeled mobile robotic systems and viewed as a singular perturbation of nonholonomic dynamics. For sufficiently strong friction forces, the dynamics emit an attractive invariant manifold interpreted as the perturbation of the constraints. This invariant manifold describes small slip velocities at the wheel contact points. We propose a systematic decomposition of the control system into slow and fast directions. The invariant manifold is approximated with a power series, which can be recursively computed. Accordingly, we develop a novel recursive procedure to input-output linearize the slow subsystem by dynamic-state feedback transformations. Using this procedure, design a trajectory-tracking PD controller to compensate for the violations of constraints and closed-loop stability analysis is performed. Our approach is illustrated through a numerical case study.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Engineering, Aerospace
- Date Created:
- 2023
-
- Resource Type:
- Thesis
- Creator:
- Meister, Curtis Harrison
- Abstract:
- Seasonal thermal energy storage (STES) could allow solar energy to offset the majority of building energy loads in cold climates. This thesis outlines one of the first long-term, full-scale experimental studies on seasonal storage at the single-detached home scale. A solar thermal system couples a large evacuated tube solar array to both short term thermal storage tanks and a 36m^3 buried water tank used for seasonal storage. Solar heat stored in these water tanks provides space heating (SH) and domestic hot water (DHW) to an energy-efficient two-storey research house in Ottawa, Canada. Long term experiments are described, including a one-year cycle of the system and long term heat loss monitoring. Results show that the as-built system can meet the majority of the building's SH and DHW loads, achieving a solar fraction of 68%. However, experiments revealed several areas of underperformance. Most prominently, faulty solar collectors limited the system's potential. To assess the true potential of the system, detailed energy models were developed and validated against experimental data. Simulated free of faults and underperforming components, the system has a predicted solar fraction of over 90%. Building simulation is further used to explore improved control and sizing of STES systems for single-detached homes. Control methods and decisions such as variable speed pumping, radiant floor supply temperature modulation, and storage setpoints are explored, among others. In regard to sizing, for the house under study, it is shown that solar fractions over 90% require relatively large (and potentially costly) STES tanks (30m^3). However, a moderately lower solar fraction of 70-80% may be obtained even with significantly smaller tanks (10m^3), provided an "oversized" solar thermal array is utilized, which may come at a significantly lower investment cost.
- Thesis Degree:
- Doctor of Philosophy (Ph.D.)
- Thesis Degree Discipline:
- Engineering, Mechanical
- Date Created:
- 2022
-
- Resource Type:
- Thesis
- Creator:
- Burtt, Damon
- Abstract:
- Flaring of gas at upstream oil and gas facilities is a globally significant problem with uncertain emissions. This thesis details a methodology to quantify flare carbon conversion efficiency and emission rates of flares subjected to turbulent crosswind within quantified uncertainties using a closed-loop wind tunnel. Experiments were performed on 1-inch to 4-inch diameter pipe flares burning methane-dominated flare gas mixtures at exit velocities of 0.5-2 m/s in turbulent winds of 2-10 m/s. Flare efficiency was modestly dependent on flare diameter and exit velocity, and highly sensitive to wind speed and flare gas composition. The strong sensitivity to gas composition, even among similar methane-dominated alkane mixtures, is surprising and confounds simple, predictive emissions models. However, the data in this thesis give new insight into emissions of flares subjected to turbulent crosswinds, and developed simple empirical models offer a first-order means to quantifying flare emissions and developing greenhouse gas inventories.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Engineering, Mechanical
- Date Created:
- 2022
-
- Resource Type:
- Thesis
- Creator:
- Bronipolsky, Andrei
- Abstract:
- This study focuses on the aerodynamic interaction of a strut and a row of guide-vanes located in the inter-turbine duct (ITD) of a typical turbofan gas-turbine engine in the context of optimizing their relative positioning to minimize the total profile loss. The study was intended to use numerical analysis to determine promising axial and pitchwise positions of the strut relative to the guide-vane row to create a test matrix for further experimental study. For this analysis, the Baseline (BSL) Reynolds-stress turbulence model was used in a series of benchmarking exercises using published and experimental low-speed wind-tunnel data. The BSL model was found to be limited in its ability to accurately generate the flow physics in a free-shear layer despite being capable of approximating the momentum thickness in the wake of a strut and guide-vane row in tandem configuration and the mixing-layer growth rate of a planar turbulent free-shear layer.
- Thesis Degree:
- Master of Applied Science (M.App.Sc.)
- Thesis Degree Discipline:
- Engineering, Mechanical
- Date Created:
- 2022