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Jose, Nikhil (author)Surfaces that induce slip at the wall have been shown to reduce skin friction drag in the turbulent regime. While superhydrophobic and liquid-infused surfaces are capable of drag reduction in turbulent hydrodynamic flows, neither would be feasible in aerodynamic applications due to the added roughness and the minuscule slip lengths created by...master thesis 2023
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Makaveev, M.K. (author), Snellen, M. (author), Smeur, E.J.J. (author)This paper puts forward a novel design for an airspeed instrument aimed at small fixed-wing tail-sitter unmanned aerial vehicles. The working principle is to relate the power spectra of the wall-pressure fluctuations beneath the turbulent boundary layer present over the vehicle’s body in flight to its airspeed. The instrument consists of two...journal article 2023
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Carrasco Grau, Julio (author)In the last decades, the prevailing belief that smooth surfaces offer the lowest drag has been challenged often. Scholars have, for example, introduced rough and modified surfaces to reduce turbulent skin friction. One of the technologies proposed in the literature is an array of chevron-shaped protrusions; however, there is no academic...master thesis 2022
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ANAND, ABHIRATH (author)The turbulent boundary layer development under the influence of an air cavity is studied experimentally using planar PIV, with the aim of gaining insight and building upon the flow physics typically encountered in the application of air layer drag reduction. A detection technique based on correlation values is implemented to obtain an...master thesis 2021
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Hartog, Friso (author)Turbulent drag is the largest source of fuel consumption in aviation and forms a significant contribution to climate warming. Recent numerical studies have suggested the ability of surfaces with streamwise-preferential permeability to reduce turbulent friction, and a theoretical framework behind the working mechanism has been proposed. This work...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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van der Voort Maarschalk, Joost (author)Drag in pipelines is composed almost solely of skin friction drag. The most common technique to achieve drag reduction (DR) is by adding drag-reducing agents. However, in the aerospace industry, various impressive passive drag-reducing techniques have been suggested to reduce skin friction drag in the past decades. Among these techniques,...master thesis 2021
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Dijkshoorn, Dominic (author)Organic Rankine Cycle (ORC) Power Plants can be of greatimportance in the energy transition as they are suitable for converting wasteheat to power and can utilize renewable energy for their operation. To improvethe efficiency of ORC Power Plants, the physical phenomena inside thesemachines must be understood....master thesis 2020
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De Petter, Christophe (author)Shock-Wave/Turbulent-Boundary Layer Interactions (SWTBLI) often occur in applications of technological interest. The associated inherent low-frequency unsteadiness dictates the use of Large-Eddy Simulation (LES) approaches to resolve the interaction, which unavoidably implies a very high computational cost. For this reason, no well-resolved long...master thesis 2019
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van Weersch, Yorin (author)Dimples are spherical indentations applied at a surface that have been found to yield a skin-friction drag reduction within a turbulent boundary layer. Shallow dimples have inherent advantages over traditional flow control techniques that require heavy active systems to be installed or pose maintenance problems. Proven drag-reducing mechanisms...master thesis 2017
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Novara, M. (author)This research deals with advanced developments in 3D particle image velocimetry based on the tomographic PIV technique (Tomo-PIV). The latter is a relatively recent measurement technique introduced by Elsinga et al. in 2005, which is based on the tomographic reconstruction of particle tracers in three-dimensional space from a small number of its...doctoral thesis 2013
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Gillissen, J.J.J. (author)Using direct numerical simulations of turbulent Couette flow, we predict drag reduction in suspensions of neutrally buoyant fluid spheres, of diameter larger than the Kolmogorov length scale. The velocity fluctuations are enhanced in the streamwise direction, and reduced in the cross-stream directions, which is similar to the more studied case...journal article 2013
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Akhavan Taheri Borojeni, A. (author)In this research the experiments were performed in the water tunnel at the Laboratory for Aero and Hydrodynamics to investigate the 3D flow structure over roughness elements as a model for the flow over urban environment. It represents the first phase in an extended study on the dispersion of pollutants in an urban environment, which process is...master thesis 2010
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Elsinga, G.E. (author)Tomographic Particle Image Velocimetry is a new experimental method developed to study three-dimensional motion in turbulent flows. The technique is an extension of standard PIV and makes use of several simultaneous views of illuminated tracer particles and their three-dimensional reconstruction as a light intensity distribution by means of...doctoral thesis 2008
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- Brand, A.J. (author) doctoral thesis 1992
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de Bruin, A.C. (author)The three dimensional flow field around delta wings with leading-edge vortex flow can be computed with panel methods. However, secondary flow separation may occur on the leeward surface of the wing. The associated free vortex sheet can be modeled in the potential flow calculation method, if the location of the secondary separation is provided by...report 1983
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Lindhout, J.P.F. (author), van den Berg, B. (author), Elsenaar, A. (author)At the workshop nine participants presented the results of their calculations for a practical test case. The test case deals with the 3D turbulent boundary layer development, including separation, on the root section of a swept wing. The employed calculation methods comprise 3D integral methods as well as field methods. A short description of...report 1981
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Kubota, H. (author)Three-dimensional glancing-shock/turbulent boundary-layer interaction has been investigated at the Cranfield Institute of Technology in two separate test programmes using a 2.5 x 2.5 inch intermittent tunnel and a 9 x 9 inch inch continuous tunnel, at a Mach number of approximately 2.5. The experimental results include oil-flow pictures, vapour...report 1980
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Dickman, C.C. (author)Starting in 1946 as the College of Aeronautics, the Cranfield Institute of Technology was granted university status in 1969. In 1993 it changed its name to Cranfield University.report 1977