Searched for: contributor:"Dwight, Richard (mentor)"
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Nieuwenhuisen, Kyle (author)
Adverse pressure gradients, separation and other forms of non-equilibrium flows are often encountered in flows of interest. In these type of flows, the Boussinesq hypothesis does not hold and often leads to erroneous predictions by eddy viscosity models. In an attempt to capture these non-equilibrium effects, lag parameter models introduce a lag...
master thesis 2020
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Luan, Yuyang (author)
In studies of wind plant designs, wake dynamics are of great interests as wakes affect downstream turbine loading that impacts wind plant efficiency. Recent developments of Tensor Basis Decision Tree (TBDT) based machine learning (ML) models in reconstructing the turbulence anisotropy fields of simple flow cases prompt the motivation in applying...
master thesis 2020
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Terleth, Niels (author)
Due to their powerful approximation capabilities, artificial neural networks have seen a wide interest in various fields. A particular application is the use of an artificial neural network to predict solutions of the governing equations for fluid flow i.e. the Navier-Stokes equations. This is done by taking the space and time variables as the...
master thesis 2019
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Raghunathan Srikumar, Sampath Kumar (author)
Large Eddy Simulations (LES) of a novel type of wing/body junction called the anti-fairing are performed in the current thesis to study the complex turbulent flow physics involved in the junction area and also to obtain a clear understanding of the drag reduction capabilities of the anti-fairing. In regards to that, two separate LES are...
master thesis 2019
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Blauw, Alexander (author)
Turbulent flows are commonly encountered in scientific research or engineering applications and need simulations to be resolved. The Navier-Stokes equations govern the simulations of turbulent flows. One of the most common ways to solve the Navier-Stokes equations is to analyse the Reynolds averaged form (RANS). Next to the increasing...
master thesis 2019
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van Korlaar, Arent (author)
Turbulence closure models will continue to be necessary in order to perform computationally affordable simulations in the foreseeable future. It is expected that Reynolds-averaged Navier-Stokes (RANS) turbulence models will still be useful with the further development of the more accurate, but computationally expensive large eddy simulation (LES...
master thesis 2019
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Fatou Gomez, Javier (author)
The computation of complex turbulent flows design optimization processes is currently limited by the lack of accuracy of Reynolds-Averaged Navier-Stokes (RANS) in massively separated flows and the infeasible cost of multiple Large-Eddy Simulation (LES) evaluations. A novel method is presented, injecting data from LES or other high-fidelity...
master thesis 2018
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van Hove, Alouette (author)
Accurate measurement of emissions (i.e. volume flow rate multiplied by concentration) is vital to the control and reduction of air pollution. We quantify the uncertainty of flow measurements by S-type pitot tubes in narrow exhaust stacks (diameter < 0.5 m) in support of recent European Union (EU) regulations for emissions from medium-size...
master thesis 2018
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Döpke, Max (author)
In this research a global-coefficient non-linear eddy viscosity model (NLEVM) is studied. This model stems from the inherent inability of the Boussinesq approximation to model anisotropy and therefore flow features such as: swirl, stream-line curvature and secondary motions (Lumley, 1970; Pope, 1975; Craft et al., 1996). The focus lies on the...
master thesis 2018
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Butler, Jacob (author)
The project concerns uncertainty reduction of parameters of a thermodynamic equation of state for a dense gas, using Bayesian inference. The dense gas considered is D6 siloxane and the equation of state used is the polytropic van der Waals equation. The shock tube data comes from the flexible asymmetric shock tube (FAST) experiment. This is...
master thesis 2018
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D' Onofrio, Federica (author)
RANS equations are nowadays widely used in industry because of their affordability in terms of computational costs. They reached a high level of complexity, as they involve systems of non-linear partial differential equations. However they still lack of generality as they are based on closure coefficients determined from fundamental real flow...
master thesis 2017
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Kotnik, Aljaž (author)
In the framework of LuFo R\&T projects a number of Rolls-Royce Deutschland Low and High Pressure Compressor rotor blades were geometrically scanned at the beginning and end of their life cycle. Based on this data component wear, ageing and manufacturing variability across the life cycle of the engine can be derived. Using Computational Fluid...
master thesis 2017
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Yoon, Woosik (author)
Reynolds Averaged Navier-Stokes turbulence models have been widely used in many industrial applications because of their lower computational cost compared to other simulation approaches such as DNS and LES. This is a consequence of considering mean-ow quantities achieved by the time-averaging process. However, the time-averaging introduces the...
master thesis 2017
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Belligoli, Zeno (author)
Junction flows occur when a boundary layer encounters an obstacle (such as a wing) on its path. They can occurr either in laminar or turbulent flow conditions but only the turbulent case is considered here. This type of flow is usually a 3D, anistoropic, unsteady, turbulent flow. These characteristics are the result of two main phenomena. The...
master thesis 2015
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Maher, Gabriel (author)
This thesis demonstrated how the Newton and BFGS algorithm could be used to solve the standard VGM relations and least-squares formulation respectively, for arbitrary forms of the _ parameter, including nonlinear _ s, appearing in the VMM. The proposed procedure were also shown to be able to handle arbitrary projectors that are compatible with...
master thesis 2014
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Kwanten, Bert (author)
Scientists and engineers use observations, mathematical and computational models to predict the behaviour of physical realities such as turbulent ows. However, as a consequence of observational errors, errors in the mathematical models and discretisation errors in the computational models, our knowledge about what happens in reality is imperfect...
master thesis 2014
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Todarello, Giovanni (author)
In the present thesis report the author synthetizes 9 months of work at the DSNA department of ONERA in Chatillon, France. The topic of the thesis is goal oriented mesh adaptation with particular application to unstructured grids and to _nite volume methods. The motivation of the present work is the application to unstructured meshes of a novel...
master thesis 2014
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Blom, David (author)
The GMRES algorithm has been discussed to solve the linear system Ax = b for application in a flow solver. Besides the conventional GMRES algorithm, several approaches are discussed which supposedly reduce the computational costs of the method, and reduce the number of iterations needed to satisfy the convergence criteria. GMRES is one of the...
master thesis 2013
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de Reus, Jasper (author)
It is investigated if a Multi Point Inflow Performance Relationship (MIPR) using Uncer- tainty Quantification (UQ) can lead to a step change in completion design. The MIPR model consists of several Kuchuk IPR models coupled with a wellbore network, and is verified against a discretized model. It is found that the assumption of artificial no-flow...
master thesis 2012
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Yildizturan, Haci (author)
Nowadays, the numerical errors are decreased to an acceptable level in the sense that the variability of the model parameters is becoming more important for obtaining results with higher reliability. Therefore, the focus of this thesis is on the quantification of the uncertainties of the turbulent closure model k −ǫ. The k −ǫ model is tuned to...
master thesis 2012
Searched for: contributor:"Dwight, Richard (mentor)"
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