Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 62 for “"TL Motor vehicles. Aeronautics. Astronautics"”.
-
INVESTIGATION OF SPOT WELDING ELECTRODE TIP WEAR AND A NON-DESTRUCTIVE TEST OF PLASTIC JOINING IN THE AUTOMOTIVE INDUSTRY
… sometimes with a chisel. Once the weld is dismantled the quality can be analysed. During the course of this thesis the chisel test, and other comparable tests were carried out. The following thesis presents an overview of electrode current selection and its variance over the lifetime of the …
-
A roadside units positioning framework in the context of vehicle-to-infrastructure based on integrated AHP-entropy and group-VIKOR
The positioning of roadside units (RSUs) in a vehicle-to-infrastructure (V2I) communication system may have an impact on network performance. Optimal RSU positioning is required to reduce cost and maintain the quality of service. However, RSU positioning is considered a difficult task due to …
-
Aerodynamic analysis of groove based vortex trap configuration on the retreating helicopter blade
… the retreating blade receives attention from countless researchers because it is an important factor in the stability of the helicopter. The retreating blade stall will effect the stability of the helicopter due to the high angle of attacks. Prouty‟s helicopter data are used in this research to …
-
A knowledge sharing framework to support rapid prototyping in collaborative automotive supply chain
In today’s global economy, competition is increasingly driven by a high rate of product renewal. In this context, with market demands for the development of high quality products at lower costs, highly customisable and with short life cycles, new technologies have been adopted by the automotive …
-
On the dynamics, navigation and control of a spacecraft formation of solar concentrators in the proximity of an asteroid
… as in the case here with the orbit being constantly altered by the deflection action and subject to perturbations, such as solar radiation pressure. Two concepts, and the corresponding dynamics and control, are presented based on previous trade-off and optimisation studies. The first uses a …
-
Investigation of S-shaped intake aerodynamics using computational fluid dynamics
Flows in the s-shaped intake (Royal Aircraft Establishment intake model 2129-M2129) have been simulated and analysed using Computational Fluid Dynamics (CFD). Various flows have been simulated from steady through-flow for validation and verification, steady flows at a variety of angles of pitch and …
-
Predicting the high-frequency airloads and acoustics associated with blade-vortex interaction
… downstream of the rotor, essentially independently of the resolution of the calculation or the blade model used. A marked improvement in accuracy of the predicted high-frequency airloads and acoustic signature of the HART II rotor is obtained when the lifting-chord model for the blade …
-
Analysis and reconstruction of dynamic-stall data from nominally two-dimensional aerofoil tests in two different wind tunnels
This work is a specific investigation into low speed aerofoils. The term “low speed” is normally used to indicate free stream velocity less than Mach = 0.5 and, here, not more than 0.2 M when considering dynamic-stall. This field of investigation, for the QinetiQ aerofoil, has been somewhat ignored …
-
Fast prediction of transonic aeroelasticity using computational fluid dynamics
The exploitation of computational fluid dynamics for non linear aeroelastic simulations is mainly based on time domain simulations of the Euler and Navier-Stokes equations coupled with structural models. Current industrial practice relies heavily on linear methods which can lead to conservative …
-
The assessment of a rotorcraft simulation model in autorotation by means of flight testing a light gyroplane
The simulation and flight testing of a light gyroplane aircraft is performed obtaining results regarding the flight dynamics attributes of the vehicle. The main aim of the work was to assess the ability of a mathematical model to simulate rotorcraft in the autorotative flight state. Additionally, …
-
Hydrofoils: design of a wind propelled flying trimaran
Abstract available: p.3-4
-
The prediction of unsteady three-dimensional aerodynamics on wind turbine blades
… stall onset on wind turbines can be correctly predicted using 2-D tools. A closer examination of the discrepancies between the predictions and measurements has highlighted the particular aerodynamic characteristics of the S809 aerofoil, utilised as the blade section of the NREL turbines. …
-
Investigation of orthogonal blade-vortex interaction using a particle image velocimetry technique
… a suitably high thickness ratio, there was little evidence to suggest that the vortex core axial flow is 'cut' by the interacting body in the manner observed for the lower thickness ratios. For lower thickness ratios, as the vortex core is blocked by the interacting blade surface, the …
-
A new appreciation of inflow modelling for autorotative rotors
A dynamic inflow model is a powerful tool for predicting the induced velocity distribution over a rotor disc. On account of its closed form and simplicity, the model is highly practical especially for studying flight mechanics and designing control systems for helicopters. However, scant attention …
-
CFD analysis and design of a low-twist, hovering rotor equipped with trailing-edge flaps
This thesis reports the analysis and design of a hovering rotor equipped with both slotted and blended trailing-edge flaps. This was accomplished by combining a simple blade element method with 3D inviscid and RANS CFD that allowed for a robust sequence of design specification, analysis, and …
-
CFD investigation of the aerodynamic performance of a single-stage and a two-stage centrifugal fan
An extensive CFD study of backward-curved centrifugal fans, manufactured by Howden, is undertaken using the commercial solver FLUENT and its associated pre-processor GAMBIT. Initially, a single-stage fan is analysed... The solution methods are used to lay the foundation for the CFD analysis of a …
-
Test-driven development of embedded control systems: application in an automotive collision prevention system
… In addition, experiments with prototype vehicles on test tracks and field tests are presented to verify the system’s functional requirements within a system testing approach. Finally, the new test-driven development process for embedded control systems is evaluated in comparison to …
-
Design, optimization and flight testing of a micro air vehicle
Micro Air Vehicles (MAVs) are a new type of aircraft maturing every year. The first mission-capable MAVs are already available on the market. Similarly to larger UAVs, MAVs may be used in a variety of applications, both military and civilian, such as situational awareness, reconnaissance, data …
-
Experimental and computational analysis for insect inspired flapping wing micro air vehicles
… the ability to fly and some seem to do so effortlessly with captivating movement. The flight characteristics of these natural fliers have greatly fascinated biologists and engineers for a long time that to this day researchers continue to actively work in this field of science with the aim of …
Page 1 of 4