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Lam, Sam (author)Wall-modeled large eddy simulations (WMLES) are becoming an increasingly viable tool to study complex unsteady turbulent flows. Conventional wall models applied in these simulations are however not applicable to laminar boundary layers. While these encompass only a tiny fraction of the total surface area, erroneous predictions in this region of...master thesis 2023
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Delaporte, Cyril (author)Hydrofoils can under certain circumstances cause a phase change from liquid water to water vapor. This phenomenon is called cavitation and is caused by the low pressure over the hydrofoil when the vessel exceeds a certain velocity though the water. Cavitation can take different forms depending the angle of attack α and the flow conditions which...master thesis 2023
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Adam, Florian (author)Maintaining laminar flow on large swept surfaces of subsonic transport aircraft, i.e. the wings and the stabilisers, is currently posing a considerable challenge for aerodynamic design. Improving the efficiency of aircraft by delaying or removing the laminar-to-turbulent transition process over the wing and tail parts can substantially reduce...master thesis 2023
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Bunk, Yannick (author)The development of a high-fidelity fluid-structure interaction tool for the simulation of aircraft flight dynamics in the subsonic flow regime is presented. The tool combines a high-fidelity large-eddy simulation code with an immersed boundary method, a multibody solver and a loose coupling scheme between fluid and solid. The development of the...master thesis 2022
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Lobato Perez, Javier (author)During a severe accident in a water-cooled nuclear power plant, large quantities of hydrogen can be generated in the reactor core. The hydrogen mixed with air presents a potential risk of combustion when the hydrogen concentration reaches flammability limits. If combustion occurs, pressure loads can damage safety systems and even compromise the...master thesis 2021
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Herrera Clapera, Miquel (author)Computational fluid dynamics is nowadays one of the pillars of modern aircraft design, just as important as experimental wind tunnel testing. Very ambitious goals in regards to performance, efficiency and sustainability are being asked of the aviation industry, the kind that warrant a virtual exploration of the edges of the flight envelope....master thesis 2021
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Raman, Raghavendran (author)Efficient combustion processes are indispensable in limiting the temperature increase to 1.5 deg C as set by Intergovernmental Panel on Climate Change (IPCC) before 2030 to curtail the effects of global warming. As for the emissions, the main task lies in controlling the air-fuel ratio in the lean regime as to control the emissions of NOx since...master thesis 2021
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Lin, Yuyu (author)Dimples are shallow, indented surfaces that attempt to reduce drag in turbulent boundary layer flows. However, the underlying effect of the dimples on the drag is not entirely understood. This thesis sets out to expand our understanding; a numerical investigation of turbulent boundary layer flow over dimpled surfaces is conducted. This research...master thesis 2021
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Shahzad, Haris (author)The location of laminar to turbulent transition is an important consideration as turbulent flow is associated with higher skin friction drag and, by extension, lower fuel economy. In unswept boundary layers, natural transition proceeds by the amplification of Tollmien–Schlichting waves. Tollmien–Schlichting waves are convective instabilities...master thesis 2020
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Başkaya, Ata (author)Atmospheric entry is a crucial phase in planetary exploration missions. During entry, the vehicle experiences severe heating at hypersonic speeds. To ensure the survival of the payload, this heating needs to be mitigated using thermal protection systems. Ablative shielding materials dissipate the incoming heat largely by surface reactions...master thesis 2020
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Brchnelová, Michaela (author)Although usually neglected in aerodynamics, radiation can present the main heat transfer mechanism in some aerodynamic applications and cause significant changes in the behaviour of the flow. Such applications typically include very high-temperature conditions such as hypersonic flow during reentry and hot gas in combustion systems. In these...master thesis 2020
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Henger, Max (author)Reynolds-Averaged Navier-Stokes (RANS) turbulence models are in widespread use in the commercial application of Computational Fluid Dynamics (CFD), but lack the capability to accurately compute unsteady flows and aeroacoustics due to its implied averaging of turbulent effects. In order to compute these kinds of flows, Large Eddy Simulation (LES)...master thesis 2020
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Maselis, Robbe (author)Compressed natural gas (CNG) has been gaining attention in the automotive industry since it allows for a substantial reduction in carbon dioxide emissions. Recent advancements in direct-injection technology have contributed to an increase in volumetric efficiency and engine power, but the physical modeling of such gaseous injection with...master thesis 2019
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Casacuberta Puig, Jordi (author)Micro-ramps are passive flow control devices used to delay flow separation. Their use is widespread due to their reduced drag and structural robustness. We reproduce with Direct Numerical Simulations (DNS) recent Particle Image Velocimetry (PIV) experiments of the micro-ramp flow performed at TU Delft to study the wake of a micro-ramp immersed...master thesis 2018
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Gnanasundaram, Arun (author)The whole construct of explicit algebraic Reynolds stress models, as they are known in RANS, is based on the weak equilibrium assumption. By employing this assumption, and in addition, incorporating models for terms in the Reynolds stress transport equations, the system of six partial differential equations can be simplified to an algebraic form...master thesis 2018
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Tsavlidis, Ioannis (author)The graduation project was conducted at the upper stage liquid propulsion department of ArianeGroup at the facilities of Airbus DS, Bremen. Based on a series of past flights of Ariane 5 launcher, the aim is to analyze the fluid motion and the pressure fluctuations in the cryogenic propulsion upper stage Liquid Hydrogen (LH...master thesis 2018
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Holtslag, Wouter (author)The Steady Laminar Flamelet Combustion Model was used in combination with the Improved Delayed Detached Eddy turbulence model. A model rocket combustor was simulated with these models. Combustion was performed with gaseous methane and oxygen, injected non-premixed. Experimental data was available for the pressure and wal heat flux to validate...master thesis 2018
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Steenbeek, Jorden (author)High-fidelity hybrid RANS/LES methods are unable to accurately predict the transition from laminar to turbulent boundary layer flows. Usually resulting in an incorrect prediction of boundary layer characteristics. In this study, a hybrid RANS/LES model was developed for transitional boundary layer flows. The transitional kkL-omega turbulence...master thesis 2017
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- Tanouti, N. (author) master thesis 2017
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Kumar, A. (author)Detailed investigation of factors that influence Wind-Tunnel modeling in vehicle thermal simulation. Tasks involved observing and investigating the additional equipment attached to the wind tunnel model that could alter the results when compared with the computational simulation results. All the study is based on computational simulation finally...master thesis 2016