document

Probabilistic Regression of wind turbine loads using Conditional Generative Adversarial Networks

Yap, Li-Toong (author)

Site analysis to determine the loads experienced by wind turbines based on site-specific environmental conditions is typically done using either coupled aero-servo-elastic simulations for onshore wind turbines or coupled aero-servo-hydroelastic simulations in the case of offshore wind turbines. These simulations become computationally expensive...

master thesis 2023

document

On leveraging physical knowledge to augment neural network-based surrogate models for simulations

Kaniewski, Tadeusz (author)

The computational cost of high-fidelity engineering simulations, for example CFD, is prohibitive if the application requires frequent design iterations or even fully fledged optimization. A popular way to reduce the computational cost and enable fast iteration cycles is to use surrogate models that are trained to predict simulation results from...

master thesis 2023

document

Local Enrichment Function Based Corrections Applied to Conventional RBF Mesh Deformation Methods

Tallapragada, Bharadwaj (author)

A popular class of methods for solving Fluid-Structure Interactions (FSI) problems computationally are the moving mesh deformation methods. These methods generally involve deforming the fluid domain so that it conforms to the structure as it undergoes changes. An efficient and robust moving mesh technique involves interpolation of displacements...

master thesis 2023

document

Low and High Fidelity Aerodynamic Simulations for Airborne Wind Energy Box Wings

Buendía Vela, Gabriel (author)

Airborne wind energy systems convert the kinetic energy of wind into usable power. In general terms, this power is proportional to the ratio CL³/CD² of aerodynamic coefficients. From a structural perspective, the thickness-to-chord ratio of conventional AWE wings needs to be high to withstand the high aerodynamic loads. The...

master thesis 2022

document

Investigation of the Dynamic Response of a FOWT to Periodic Surge Motion

Uritsky, Vadim (author)

Due to the increasing interest in modelling floating offshore wind turbines, simulation tools need to be adapted from fixed-base applications to surge applications. In this study, an open-source inviscid 3D panel method named Vortexje was adapted for surge motion and its ability to capture the physics of severe surge motion (when the rotor...

master thesis 2021

document

Efficient Long Term CFD Simulation of the Tri-Floater Using ComFLOW

Vriends, Calvin (author)

One of the emerging technologies in sustainable energy is Floating Offshore Wind. GustoMSC designs a structure for Floating Offshore Wind, the Tri-Floater. One of the problems that need to be investigated before building the unit is wave impact loading. Wave impact occurs when a large wave hits the structure, placing large forces on the...

master thesis 2021

document

Reducing production cost in offshore wind turbine tower design

Nekeman, Olaf (author)

The objective of the thesis was to evaluate the cost reductions and tower design when production costs are included in the design process of an offshore wind turbine tower. First, a tower cost model had to be developed. Then, based on the findings, a cost optimization model was built with the tower design software from Siemens Gamesa Renewable...

master thesis 2021

document

Application of Acoustic Metamaterials in Boundary Layer Instability Control

de Koning, Coert (author)

To achieve delay of laminar-to-turbulent transition of boundary layers, the application of acoustic metamaterial concepts is investigated. This is done analytically, numerically and experimentally by studying the interaction between a Helmholtz resonator and a TS wave. A Helmholtz resonator can serve as a meta-atom in a metamaterial. The desired...

master thesis 2021

document

Wind Farm Layout Optimisation Under Uncertainty Using Surrogate Models

Chuang, Jia Shian (author)

This research aims to develop a method to create a wind farm layout that is robust against the uncertainty source, the inter-year variation of Weibull parameters and wind direction sector probabilities. A wind farm layout optimisation problem under uncertainty corresponds to optimisation under uncertainty (OUU), which is computationally...

master thesis 2020

document

Design of a Variable Pitch, Energy-Harvesting Propeller for In-Flight Power Recuperation on Electric Aircraft

van Neerven, Matthijs (author)

In this thesis project, it is investigated to what extent the energy consumption of an electric aircraft can be improved by using a variable pitch and RPM propeller, including energy recuperation during the descent, with respect to a constant pitch propeller. The largest percentage of total mission energy saved using the variable pitch propeller...

master thesis 2020

document

The Design of a Small Aeroacoustic Wind Tunnel

Vendrig, Perrin (author)

In this master thesis project the initial steps for the design of a new wind tunnel<br/>for aeroacoustic measurements are made. Well-documented sizing methods for<br/>different wind tunnel parts were found in a literature study and were used<br/>together with 2D CFD simulations to create a new wind tunnel design. Thick<br/>corner vanes were used...

master thesis 2020

document

Noise-augmented offline training of ANN unresolved-scale models

Pusuluri, Abhinand (author)

An effective way to solve the forced Burgers' equation in a variational multiscale framework is to close the system of equations using unresolved-scale interaction terms predicted by an artificial neural network. The goal of this thesis is to investigate the accuracy and stability of the said system by training a neural network offline with data...

master thesis 2020

document

Machine Learning of Wind Plant Turbulence Anisotropy Fields

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

document

Experimental Characterization and Analytical Modelling of Rotor Tonal Noise

Deora, Chakshu (author)

Rotors have played a huge role in the history of the aerospace industry. It is being widely used in small scale aircraft, helicopters, ships, wind turbines, to name a few. The study of noise generated by the rotors is an important subject of research. This project aims to characterize the open rotor tonal noise using the experimental and...

master thesis 2019

document

Design and Optimisation Framework of a Multi-MW Airborne Wind Energy Reference System

Eijkelhof, Dylan (author)

In the present world of conventional wind energy, the National Renewable Energy Laboratory (NREL) 5MW reference wind turbine for offshore system development has become an important piece of the puzzle towards a renewable future based on wind energy. DTU showed the benefit of such a reference model with their 10 MW reference wind turbine and...

master thesis 2019

document

Experimental Investigation of Fan-Stage Interaction Noise of a Turbofan Engine

Kalyani, Sidharth Krishnan (author)

Future designs of turbofan engines are heading towards High By-Pass Ratios (HBPR) to satisfy the requirements of improving the overall efficiency, but there is an inherent acoustic penalty related to this. An increase in the by-pass ratio imposes structural constraints on the engine leading to a decrease in the axial distance between the rotor...

master thesis 2019

document

Characteristics of Offshore Wind Farm Wakes and their Impact on Wind Power Production from Long-term Modelling and Measurements

Langor, Erin (author)

As the penetration of offshore wind farms continues to increase in Western Europe, the North Sea in particular is becoming more densely populated by offshore wind farms. Wind turbine wakes have been a topic of great research in the field of wind energy for some time, however the industry now seeks an understanding of the in- fluence of the wake...

master thesis 2019

document

CFD Study of Piston Cooling Using Oil Jets

Venkatesh, Vishal (author)

For heavy duty diesel engines, piston temperature control is very important in constructing a successful design that meets the demands of increasing power output and stringent emission regulations. Overheating of piston is avoided with engine oil through spray cooling and gallery cooling processes. In this research project, evolution and...

master thesis 2019

document

Tip vortex modelling for cavitation noise applications: A verification and validation study in ReFRESCO

Liebrand, Rens (author)

Cavitating tip vortices of marine propellers are the main contributors to underwater radiated ship noise due to their dynamic behavior and broadband sound spectrum. Experimentally, it is challenging to get a detailed insight into the vortex structure which makes it difficult to understand the noise generating mechanisms. Although Computational...

master thesis 2019

document

Latent Space Modelling of Unsteady Flow Subdomains: Thesis Report

Mulder, Boris (author)

Very complex flows can be expensive to compute using current CFD techniques. In this thesis, models based on deep learning were used to replace certain parts of the flow domain, with the objective of replacing well-known regions with simplified models to increase efficiency. To keep the error produced by the deep learning model bounded, a...

master thesis 2019