Effective solvent extraction incorporating electromagnetic heating is a relatively new concept that relies on Radio Frequency heating and solvents to replace steam in current thermal processes for the purpose of extracting bitumen from oil rich sands. The work presented here will further the understanding of the near wellbore flow of this two phase system in order to better predict solvent vaporization dynamics and heat rates delivered to the pay zone. This numerical study details the aspects of phase change of immiscible, two component, liquid/vapor systems confined in porous media heated by electromagnetic radiation, approximated by a spatially dependent volumetric heat source term in the energy equation. The objective of this work is to utilize the numerical methodology presented herein to predict maximum solvent delivery rates to a heated isotropic porous matrix to avoid the over-saturation of the heated pay zone. The total liquid mass content and mean temperature in the domain are monitored to assess whether the liquid phase is fully vaporized prior to flowing across the numerical domain boundary. The distribution of the volumetric heat generation rate used to emulate the physics of electromagnetic heating in the domain decays away from the well bore. Some of the heat generated acts to superheat the already vaporized solvent away from the interface, requiring heat delivery rates that are many times greater than the energy required to turn the liquid solvent to vapor determined by an energy balance. Results of the parametric study from the pay zone simulations demonstrate the importance of the Darcian flow resistance forces added by the porous media to stabilize the flow being pulled away from the wellbore in the presence of gravity. For all cases involving an increase in solvent delivery rate with a constant heat rate, the permeability range required for full vaporization must decrease in order to balance the gravitational forces pulling the solvent from the heated region. For all conditions of permeability and solvent delivery rates, sufficiently increasing the heat rate results in complete vaporization of the liquid solvent. For the case of decreasing solvent delivery rate, a wider range of higher permeabilities for a given heat rate can be utilized while achieving full vaporization. A three dimensional surface outlining the transition from partially vaporized to fully vaporized regimes is constructed relating the solvent delivery rate, the permeability of the porous near wellbore zone and the heat rate supplied to the domain. For the range of permeabilities ~3000mD observed in these types of well bores, low solvent delivery rates and high heat rates must be utilized in order to achieve full vaporization.

Self propulsion modelling is important in order to accurately simulate ships and submarinesusing Computational Fluid Dynamics (CFD). However, fully resolved simulations of hull andpropeller geometries are computationally heavy and time consuming. As such there is a greatinterest in lower order CFD models of propellers. This work investigates three lower ordermodels of a non-cavitating generic submarine propeller (INSEAN E1619) in OpenFOAM. Themodels investigated are Actuator Disk (AD). Rotor Disk (RD) and Actuator Line Model (ALM).The AD model applies a momentum change based on propeller performance coefficients overa disc cell set. The RD uses Blade Element Method (BEM) to calculate a more realistic thrustdistribution over the disk. Finally the ALM applies BEM over seven rotating lines within the cellset disc. The source code to the RD model was modified according to suggestions provided fromearlier studies on the model. The ALM used was originally designed for turbines which wasrectified by changing the force projection vectors in the source code to model propellers instead.There was not enough published data to directly utilize BEM on the E1619 propeller, thus thedata was generated by conducting 2D simulations on every element. The simulations were setup to replicate results provided in earlier works with higher order models in order to compareboth quantitative and qualitative results. It was found the ALM matched the reference databest out of the models tested in this work. The RD was qualitatively similar to the time averageof the ALM fields but numerically inaccurate. The AD results were poor, both quantitativelyand qualitatively.

In the field of heavy-duty vehicles, fuel efficiency and environmental protection are factors that need to be focused on, while the aerodynamic drag generated during vehicle travelling is one of the most influential aspects. This thesis delves into the aerodynamic simulation of Scania trucks using the open-source Computational Fluid Dynamics (CFD) tool, OpenFOAM v2206. This study rigorously investigates the aerodynamics of two Scania truck models under different operating conditions, including scenarios with different crosswind environments at high speeds.The core of this study is to compare and analyse the computational results of OpenFOAM v2206 and its predecessor OpenFOAM v3.0+ in a number of aspects, in order to elucidate the evolution and improvement of CFD techniques and their practical impact on vehicle simulation performance. In order to save computational resources, the RANS method was used for the steady-state simulations. Preliminary comparisons were also made with results from PowerFLOW, another CFD software widely used within the Scania group.Another important part of this thesis is the exploration of an alternative meshing method (ANSA Hextreme Mesh) in CFD simulations. As a widely used pre-processing software in the Scania group today, analysing and comparing the advantages and disadvantages of ANSA and OpenFOAM in terms of meshing, such as the ease of meshing and the accuracy of aerodynamic predictions, can help to provide valuable guidance for the application of truck shape design and aerodynamic simulation.The results indicate that OpenFOAM v2206 excels in predicting aerodynamics and has utility in optimising truck design. Compared to OpenFOAM v3.0+, OpenFOAM v2206 shows smaller discrepancies in results with PowerFLOW. Further exploration is required regarding transient simulations using OpenFOAM. In terms of meshing methods, a simplified model (Allan Body) was investigated, and there is further research to be done on meshing the complete truck.In conclusion, this thesis presents a comprehensive and in-depth exploration of truck aerodynamics using advanced CFD tools. The results not only deepen the understanding of airflow dynamics around heavy vehicles, but also pave the way for the development of more aerodynamically efficient and environmentally friendly truck designs.

Spillways are hydraulic structures that allow dams to release and convey surplus water or flood from the reservoir to the downstream channel. The spillway is a safety structure that prevents the overtopping of the dam. Many dam failure disasters were due to the inadequate capacity of the spillway, which fully illustrates the prominence of spillway design. According to the control structure, spillways can be divided into gated and ungated type. The gated spillway provides better control of the managed water level and reduces the elevation of the top of the dam. Researchers have mostly used experimental models to investigate these two types of spillways in previous literature. In the past few years, following the rapid development of numerical simulation technology, there have been more studies on the numerical modeling of spillways. However, most of the literature was about ungated spillways and most of it considered the case of low head ratios, while the case with gates, especially the case of vertical plane gates, was less investigated. In this study, the hydraulic characteristics, such as velocity, pressure, and discharge coefficient, of the ungated and gated ogee spillways are investigated by means of physical and numerical models for the case of low and high head ratios. The study covered head ratios varying from 1.4 to 4.6 and the relative gate-openings varying from 0.5 to 2. The second main objective of this study was to evaluate the performance of the numerical model to simulate gated and ungated spillways. It mainly employed 2DV OpenFOAM to simulate three turbulence models (realizable k-ε, RNG k-ε, k-ω SST), and the results were compared and calibrated with the experimental results from the physical model tests performed by the author to verify the performance of the numerical model. This study aims to demonstrate that the numerical model can be used as a complementary tool to the physical model to measure the hydraulic performance of ogee spillways.

Recent tsunami events have inflicted devastating damage to coastal communities. Existing design standards provide a certain level of evaluation of tsunami effects such that critical infrastructure can be designed to resist tsunamis. Tsunami momentum flux, used to design structures is a function of water level height and velocity of tsunami bores. Understanding tsunamis and developing mitigation measures is essential. So far, some mitigation measures have been suggested, and to improve them, further investigations are required. The design of tsunami inundation effects mitigation canals is one of the suggested solutions which has received limited attention. The first objective of this study was to investigate the effects of a rectangular canal on the hydrodynamics of turbulent bores before and after the canal by conducting a series of physical experiments. A dam-break wave was used to simulate the tsunami-like turbulent waves passing over a smooth and horizontal surface, in the presence and/or absence of a canal. Three canal water depths were used to model shallow, moderate, and deep conditions, and three canal widths were also selected to model narrow to wide conditions while the dam break waves were generated from three different impoundment depths in a reservoir located upstream of the canal. The dam-break wave propagation over a horizontal, dry, and smooth bed revealed four regimes describing the variations of bore height with time. The time to reach the maximum bore height and the quasi steady-state regime were correlated with each impoundment depth and an empirical formulation was proposed to estimate the onset of the quasi steady-state flow. The maximum bore heights measured before and after the mitigation canal location were approximately 40 % and 50 % respectively, higher compared with those recorded in the corresponding tests without the presence of a canal. The second objective of this study was to experimentally investigate the effects of canal depth on the time history of bore height and its velocity. The experimental results were used for calibration and validation of a developed numerical model. The rapid release of an upstream impoundment water depth was employed to generate a bore analogous to a tsunami-induced inundation. The time histories of wave heights and velocity were measured upstream and downstream of the canal. The recorded time-series of the water surface levels and velocities were compared with the simulation results and good agreement was found between experimental and numerical water surface profiles using a Root Mean Square Error (RMSE) and the Relative Error. Three turbulence models:, namely the standard k-ε, the Realizable k-ε, and the RNG k-ε were tested, and it was found that all turbulence models perform well but the standard k-ε model provided satisfactory accuracy. The velocity contour plots for shallow, medium, and deep mitigation canals showed the formation and evolution of jets of different characteristics. The energy dissipation and air bubble entrainment of the tsunami bore, as it plunged into a canal, increased as the canal depth increased, and the jet flow of the maximum bore velocity decreased with increased canal depth. It was found that the eye of the vortex in the canal moved steadily in the downstream direction. Generally, the bore fully plunged almost nearly into the middle of the canal and started to divide into two small vortices. The third objective of this study dealt with a sequence of numerical experiments conducted to investigate the impact of mitigation canals on the hydrodynamics of a tsunami-like turbulent bore moving across a flat bed. The effects of mitigation canal depth and its orientation on the reduction of maximum specific momentum and energy of turbulent bores crossing over it were investigated numerically. Variations in the ratio between the downstream and upstream maximum specific momentum and mean flow energy decreased as the canal depth increased, and the time history of the mean flow energy over a canal with a rectangular endwise profile revealed that the canal depth affects the jet stream of the maximum mean flow energy. As the canal depth increased, the period of time needed to dissipate the area of the jet stream with the maximum turbulent kinetic energy, vorticity, and energy dissipation rate decreased. Both the angled and perpendicular to flow direction canals caused the maximum specific momentum and energy of the turbulent bore to decrease downstream of the canal. The specific momentum and energy achieved their highest values for a canal orientation of 45º. The greatest reductions in maximum specific momentum for turbulent bores over canals with different depths and orientations were achieved for 𝜃 = 30°.

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