The World Health Organization estimates that over two billion people did not have access to a toilet in 2017. The dejects produced often end up in bodies of water and, as one in every ten crops is watered with wastewater, this is estimated to cause half a billion deaths per year. There are currently many initiatives to reach this sanitation Global Goal, including those from people such as Bill Gates and projects such as The Solar Project. The Solar Project is based in South Africa and is based on cooperation between various companies which provides them with the different components for the installation of Resource Centers, that produce fertilizers of human waste. One of the components of these Resource centers are dry-toilets, which are provided by SUPERFUNKYFUTURE. This thesis is about an analysis of a toilet model and building a function tree, performing a 2D Volume of Fluid simulation on it to see even more critical geometries. Each one of those geometries had one alteration designed. These alterations were also combined into different models and they were all tested in both 2D and 3D simulations. The results from the simulations were then post-processed in CFD-Post and animated, to allow the qualitative analysis to be performed through a Pugh Matrix and decide between designs to recommend an improved internal geometry to SUPERFUNKYFUTURE. / Världshälsoorganisationen, WHO, beräknar att mer än två miljarder människor inte hade tillgång till toaletter 2017. Avföringen från dessa människor hamnade ofta i sjöar och floder och det vattnet användes sedan i sin tur för bevattning av grödor. Detta beräknas vara orsaken till en halv miljard dödsfall per år. Det finns för tillfället många initiativ att uppnå det globala målet för rent vatten och sanitet för alla, däribland arbetar Bill Gates och projekt så som “Solar Project”. “Solar Project” har sin bas i Sydafrika och är ett samarbete mellan flera företag som tillhandahåller olika komponenter som krävs för att skapa resurscenter, som kan användas för att producera gödsel av mänsklig avföring. En av komponenterna för dessa resurscenter är torrtoaletter som är försedda av SUPERFUNKYFUTURE. Denna tes handlar om att analysera en toalettmodell, bygga ett funktionsträd, utföra en 2D “Volume of Fluid”-simulering för att upptäcka kritiska geometrier. Varje sådan geometri fick en ändring designad. Dessa förändringar kombinerades till olika modeller som sedan blev testade med både 2D- och 3D-simuleringar. Resultaten från simuleringarna blev sedan bearbetade i CFD-Post och blev animerade, detta för att möjliggöra en kvalitativ analys genom en konceptviktningsmatris. Från Konceptviktningsmatrisen kunde man välja mellan designerna och rekommendera en förbättrad intern geometri till SUPERFUNKYFUTURE.

Cette étude porte sur l'utilisation conjointe (appelée ” couplage ”) de modèle de turbulence à grandes échelles LES (Large Eddy Simulation) et du modèle multiphasique VOF (Volume of Fluid). Cette utilisation conjointe est nécessaire dans de nombreuses applications industrielles comme celles de l'automobile où l'on recherche par exemple à évaluer les prestations diphasiques de l'auvent liées au phénomène d'entraînement et d'ingestion d'une nappe d'eau par le HVAC (système d'air conditionné). Cependant, l'utilisation conjointe de ces méthodes nécessite un traitement particulier de la turbulence proche de la surface liquide afin de reproduire convenablement la quantité de mouvement transmise depuis la phase gazeuse, motrice, jusque dans la phase liquide. Basée sur une approche numérique et expérimentale, notre étude est articulée autour de trois axes. Tout d'abord, le développement de techniques de mesures spécifiques pour l'étude expérimentale de notre problématique: le LeDaR pour mesurer les déformées d'une interface et la PIV d'interface afin d'accéder aux champs de vitesse et de turbulence dans chacune des deux phases. Le second axe est la constitution d'une base de données expérimentales sur une configuration de type jet impactant sur une surface liquide représentative des phénomènes rencontrés dans l'auvent. Enfin, le troisième axe de travail est l'évaluation des modèles existants dans le code Ansys Fluent et à partir de cette analyse le développement et la validation de modèles de couplage LES-VOF. L'évaluation des modèles développés a permis de valider une stratégie de calcul adaptée aux simulations de l'entraînement d'une surface d'eau par un écoulement d'air turbulent.

In thermal spraying, semi-molten (or partially-melted) particles are likely to form when the sprayed particles are insufficiently heated, or when a composite material is deposited. The present 2D model serves to begin to assess the spreading behavior of a semi-molten particle when impacting a solid substrate. An Immersed-Boundary (IB) scheme was implemented in an axisymmetric fluid model to simulate fluid flow in the presence of a solid core. The IB method calculates a forcing term, which is added to the momentum equation, to enforce the no-slip boundary condition at the core surface. Results are presented for the impact of a semi-molten tin droplet of radius R for a wide range of solid core radii r, varying the drop size ratio r/R, and the impact velocity Uo.

In thermal spraying, semi-molten (or partially-melted) particles are likely to form when the sprayed particles are insufficiently heated, or when a composite material is deposited. The present 2D model serves to begin to assess the spreading behavior of a semi-molten particle when impacting a solid substrate. An Immersed-Boundary (IB) scheme was implemented in an axisymmetric fluid model to simulate fluid flow in the presence of a solid core. The IB method calculates a forcing term, which is added to the momentum equation, to enforce the no-slip boundary condition at the core surface. Results are presented for the impact of a semi-molten tin droplet of radius R for a wide range of solid core radii r, varying the drop size ratio r/R, and the impact velocity Uo.

With the increasing reliance and use of sensors to improve the capabilities of modern road vehicles, ensuring their functionality during different weather conditions has become an important design consideration. The sensing equipment is utilized for a multitude of tasks, ranging from aiding the user with parking to avoiding potentially dangerous situations. If the sensory equipment's functionality is compromised, these additional features might fail. Various solutions are used to ensure the integrity of the sensing equipment, primarily the location of the sensor is chosen to minimize contamination. However, in certain situations, exposure to contaminants cannot be avoided, and active cleaning systems are utilized to mitigate the issue. These systems often contain some sort of cleaning nozzle that sprays liquid onto the sensor in question.  At Volvo Cars Corporation (VCC), the group of Contamination & Core CFD is responsible for assessing the vehicle performance when exposed to contamination, such as rain, snow, or dust. This task is accomplished by employing tools such as computational fluid dynamics (CFD), and experiments. In the first part of this thesis, physical tests were conducted in the VCC wind tunnel to assess the performance of a cleaning nozzle mounted on a side-view mirror at different vehicle speeds. With the knowledge gained during the experiments, the second part of the thesis focused on the development of a cost-effective computational method that could be used to evaluate the cleaning performance virtually. The novel computational method utilized a hybrid approach, including volume of fluid simulations, discrete particle modeling, and Eulerian wall film modeling. Different analysis tools and approaches were used to extract quantitative information from the inherently qualitative data obtained from the experiments, which was then compared against the results from the computational method. The computational method was evaluated for different incoming wind velocities, and three metrics were compared to investigate if any could predict the cleaning performance seen in the experiments. At low incoming wind velocities, an accumulated film mass metric exhibited a good correlation with the experimental data. However, at higher wind speeds, an accumulated film momentum metric showed the closest correlation.

<p>At present, caused by a large amount of wave energy resources and huge energy capacity, the development and utilization of wave energy have come to be an essential development focus of wave energy manufacturing. The purpose of this research is to simulate the ocean in an offshore environment. A three-dimensional computational fluid dynamics (CFD) model was used to analyze the propagation of ocean waves. The Volume of Fluid (VOF) multiphase model and laminar model were used to analyze wave propagation in offshore conditions. Function Methodology and Mobile Methodology were implemented by applying User Defined Function (UDF) code which characterizes transient velocity profile. The parametric study was performed to analyze how velocity and amplitude change. The models were first validated by comparing them with previous analytical wave solutions. To prevent the reflection of the wave, a damping term was added by using User Define Function to define the viscosity of the water phase.</p>

Within the course of the master thesis project, two thermal phase change models for direct contact conden-sation were developed with different modeling approaches, namely interfacial heat transfer and combustionanalysis approach.After understanding the OpenFOAM framework for two phase flow solvers with phase change capabilities,a new solver, including the two developed models for phase change, was implemented under the name of interPhaseChangeCondenseTempFoam and analyzed in a series of 18 tests in order to determine the physicalbehavior and robustness of the developed models. The solvers use a volume-of-fluid (VOF) approach withmixed fluid properties.It has been shown that the approach with inter-facial heat transfer shows physical behavior, a strong timestep robustness and good grid convergence properties. The solver can be used as a basis for more advancedsolvers within the phase change class.

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