Optimization of a Multi-Element Airfoil for a Rigid Airborne Wind Energy Kite

Airborne wind energy (AWE) systems benefit from a high lift airfoil to increase the power output, to that end, multi-element airfoils are investigated for AWE applications. This thesis aims to optimize a multi-element airfoil for a rigid AWE kite that operates in a pumping cycle. Since the kite has distinct operational phases, i.e., reel-out and...

Best integer equivariant position estimation for multi-GNSS RTK: A multivariate normal and t-distributed performance comparison

The best integer equivariant (BIE) estimator for the multivariate t-distribution was introduced in Teunissen (J Geod, 2020. https://doi.org/10.1007/s00190-020-01407-2), where it was shown that the BIE-weights will be different from that of the normal distribution. In this contribution, we analyze these BIE estimators while making use of multi...

2D modeling approach for propeller-wing-flap interaction

There is renewed interest into propeller-driven aircraft to improve fuel economy. Some novel concepts such as distributed electric propulsion (DEP) use propellers for lift augmentation. Low-order methods are required to quickly determine designs with improved high-lift performance. A 2D tool may be required to “tune” a 3D inviscid model such as...

A mean-squared-error condition for weighting ionospheric delays in GNSS baselines

Although ionosphere-weighted GNSS parameter estimation is a popular technique for strengthening estimator performance in the presence of ionospheric delays, no provable rules yet exist that specify the needed weighting in dependence on ionospheric circumstances. The goal of the present contribution is therefore to develop and present the...

Holistically improving screening decisions under uncertainty in aircraft conceptual design and technology assessment: Insights on bottom-up uncertainty quantification and propagation and integrated socio-technical group decision making

In the highly uncertain environment of conceptual aircraft design and technology assessment and selection, making good decisions is of utmost importance. Aiming to contribute to improving decision quality, the problem was researched from both a technical as well as a socio-psychological perspective. In the technical perspective, the uncertainty...

MSE-impact of PPP-RTK ZTD estimation strategies

In PPP-RTK network processing, the wet component of the zenith tropospheric delay (ZTD) cannot be precisely modelled and thus remains unknown in the observation equations. For small networks, the tropospheric mapping functions of different stations to a given satellite are almost equal to each other, thereby causing a near rank-deficiency...

Uniaxial Acoustic Vector Sensors for direction-of-arrival estimation

In this paper, a specific reduced-channel Acoustic Vector Sensor (AVS) is proposed comprising one omni-directional microphone and only one particle velocity transducer, such that it can have an arbitrary orientation. Such a reduced transducer configuration is referred to as a Uniaxial AVS (U-AVS). The DOA performance of an array of U-AVSs is...

Surrogate Modelling for Airfoil Shape optimization

Airfoil optimizations require costly high-fidelity solvers. By replacing the expensive solver with a cheap to evaluate surrogate model genetic optimization becomes feasible and a global optimum can be obtained. This thesis investigates applicability of surrogate model based optimization for airfoil optimization and provides recommendations...

Ready for Take-Off: Scaled Flight Testing

Atmospheric free flight scaled flight testing is an affordable way to investigate the dynamic properties of an aircraft, while enabling a wider range of test possibilities than a windtunnel. This research is the first step into the development of a scaled flight testing model and as such will highlighted the difficulties and discrepancies which...

Boundary layer suction configurations with minimal pump requirements for multi-element airfoils

High lift systems are indispensable but complex and heavy systems so new methods to allow lighter and simpler high lift systems are actively sought after. One of the methods that have already proven to be able to increase high lift performance is boundary layer suction. In practice however the application of it is uncommon mainly due to the...

Mathematical Modelling of Nucleating and Growing Precipitates: Distributions and Interfaces

Steels with higher strength and better formability are increasingly required by the automotive industry because they can provide higher safety, reduce energy consumption and thus lead to a better environmental protection. To meet these requirements, it is a sustainable effort for steel industry to develop high strength formable steels. One of...

Making a living out of the wind: A practical approach for RIWIK to enter the rural MSE market in Kenya

In rural areas in Kenya, only 6% of the rural population has access to electricity. Hence there is a large market for electricity solutions such as solar and wind power. RIWIK is Dutch start-up that produces and sells Small Wind Turbines (SWTs) in Kenya. An SWT can produce enough electricity for one family or business. RIWIK’s business is based...

Buffet envelope prediction of transport aircraft during the conceptual design phase

During conceptual design a problem arises when predicting the buffet onset boundary. Due to the pressure on payload-range and cruise altitude capability, improvement on the buffet onset boundary is often of great importance. It is one of the primary constraints in establishing the low and transonic speed performance capabilities of transport...