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Vesper, J.E. (author)Physical Vapor Deposition (PVD) is the resublimation of a substance on a cold surface coating it with a thin solid layer. PVD coatings are utilized in industry to modify surface properties and appearance. Since the industrial process requires vacuum conditions, it has been mainly conducted in a batch process. Recently, PVD is considered a...doctoral thesis 2022
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Bugeat, B. (author), Robinet, J. Ch (author), Chassaing, J. C. (author), Sagaut, P. (author)Resolvent analysis is used to study the low-frequency behaviour of the laminar oblique shock wave/boundary layer interaction (SWBLI). It is shown that the computed optimal gain, which can be seen as a transfer function of the system, follows a first-order low-pass filter equation, recovering the results of Touber & Sandham (J. Fluid Mech....journal article 2022
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Hu, W. (author), Hickel, S. (author), van Oudheusden, B.W. (author)The flow over a forward-facing〉 step (FFS) at Ma<sub>∞</sub> = 1.7 and Re<sub>δ0</sub> = 1.3718 × 10<sup>4</sup> is investigated by well-resolved large-eddy simulation. To investigate effects of upstream flow structures and turbulence on the low-frequency dynamics of the shock wave/boundary layer interaction (SWBLI), two cases are considered:...journal article 2022
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Hu, W. (author), Hickel, S. (author), van Oudheusden, B.W. (author)The low-frequency unsteady motions behind a backward-facing step (BFS) in a turbulent flow at and are investigated using a well-resolved large-eddy simulation. The instantaneous flow field illustrates the unsteady phenomena of the shock wave/boundary layer interaction (SWBLI) system, including vortex shedding in the shear layer, the flapping...journal article 2021
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Hu, W. (author)The backward/forward-facing step (BFS/FFS) is one of the canonical geometries in aerospace engineering applications, the flow field over which has attracted extensive attention in the past decades. In a supersonic flow, laminar-to-turbulent transition and shock wave/boundary layer interaction (SWBLI) can occur over these configurations, which...doctoral thesis 2020
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Martelli, E. (author), Saccoccio, L. (author), Ciottoli, P. P. (author), Tinney, C. E. (author), Baars, Woutijn (author), Bernardini, M. (author)A delayed detached eddy simulation of an overexpanded nozzle flow with shock-induced separation is carried out at a Reynolds number of, based on nozzle throat diameter and stagnation chamber properties. In this flow, self-sustained shock oscillations induce local unsteady loads on the nozzle wall as well as global off-axis forces. Despite...journal article 2020
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Laguarda, L. (author), Hickel, S. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author)The response of asymmetric and planar shock interactions to a continuous excitation of the lower incident shock is investigated numerically. Incident shock waves and centred expansion fans are generated by two wedges asymmetrically deflecting the inviscid free stream flow at Mach 3. The excitations mechanisms considered are (i)Â pitching of...journal article 2020
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Xue, S. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author), Wang, Chengpeng (author), Shi, Zhiwei (author), Cheng, Keming (author)In this paper the configurations of shock wave-boundary layer interactions (SWBLI) are studied theoretically and experimentally in Mach number 2 and 2.5 flows on test models with various wedge angles ranging from to. The proposed theoretical method couples the free interaction theory (FIT) with the minimum entropy production (MEP) principle...journal article 2020
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Lukyanov, A. (author)N many fields of science and engineering, such as fluid or structural mechanics, and nanotechnology, dynamical systems at different scale need to be simulated, optimized or controlled. They are often described by discretizations of systems of nonlinear partial differential equations yielding high-dimensional discrete phase spaces. For this...doctoral thesis 2019
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Giepman, R.H.M. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author)High-resolution particle image velocimetry measurements were performed on laminar and transitional oblique shock wave reflections for a range of Mach numbers (M D 1:6-2:3), Reynolds numbers (Re<sub>xsh</sub> D 1.4×10<sup>6</sup>-3.5×10<sup>6</sup>) and flow deflection angles (θ 1°-5° or p3=p1 D 1.11-1.64). The laminar interactions revealed a...journal article 2018
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Pasquariello, Vito (author), Hickel, S. (author), Adams, Nikolaus A. (author)We analyse the low-frequency dynamics of a high Reynolds number impinging shock-wave/turbulent boundary-layer interaction (SWBLI) with strong mean-flow separation. The flow configuration for our grid-converged large-eddy simulations (LES) reproduces recent experiments for the interaction of a Mach 3 turbulent boundary layer with an impinging...journal article 2017
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Souverein, L.J. (author), Bakker, P.G. (author), Dupont, P. (author)A model based on mass conservation properties is developed for shock-wave/boundarylayer interactions (SWBLIs), aimed at reconciling the observed great diversity in flow organization documented in the literature, induced by variations in interaction geometry and aerodynamic conditions. It is the basis for a scaling approach for the interaction...journal article 2013
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Guardone, A. (author), Zamfirescu, C. (author), Colonna, P. (author)Modern thermodynamic models indicate that fluids consisting of complex molecules may display non-classical gasdynamic phenomena such as rarefaction shock waves (RSWs) in the vapour phase. Since the thermodynamic region in which non-classical phenomena are physically admissible is finite in terms of pressure, density and temperature intervals,...journal article 2009
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Colonna, P. (author), Guardone, A. (author), Nannan, N.R. (author)This paper presents a new class of Bethe-Zel’dovich-Thompson fluids, which are expected to exhibit nonclassical gasdynamic behavior in the single-phase vapor region. These are the linear and cyclic siloxanes, light silicon oils currently employed as working fluids in organic Rankine cycle turbines. State-of-the-art multiparameter equations of...journal article 2007
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Chao, G. (author), Smeulders, D.M.J. (author), Van Dongen, M.E.H. (author)Acoustic experiments on the propagation of guided waves along water-filled boreholes in water-saturated porous materials are reported. The experiments were conducted using a shock tube technique. An acoustic funnel structure was placed inside the tube just above the sample in order to enhance the excitation of the surface modes. A fast Fourier...journal article 2006
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Elsinga, G.E. (author), Van Oudheusden, B.W. (author), Scarano, F. (author)In compressible flows particle imaging, as done in Particle Image Velocimetry (PIV), is far from trivial. The inhomogeneous refractive index field can cause aero-optical aberrations including blurring of the image, especially near optical interfaces such as shock waves. The understanding of the process causing particle image blur (or blurring of...conference paper 2005
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van der Vooren, J. (author), van der Wees, A.J. (author)The mathematical background is described of a method that is currently being developed at NLR to calculated wave drag in transonic potential flow. The method is a generalization and extension of Garabedian's and McFadden's idea of determining wave drag by volume-integration of the artificial viscosity. The generalization of Garabedian's and...report 1990
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Boerstoel, J.W. (author)A survey of numerical methods for the calculation of inviscid Euler flows is presented. This survey has been prepared for AGAKD FDP WGOT: "Test cases for steady inviscid transonic or supersonic flows". The survey is augmented by a short assessment of the usefulness of the methods. For aerodynamic applications, the existing methods are in a...report 1983
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Jordaan, J.M. (author)Explosion waves were simulated by plunging a parabolic surface of revolution in and out of an indoor t est basin 3 feet deep by 92 feet square. These impulsively-generated Water waves are found to be dispersive as evident from the following properties : The period and the celerity of the individual waves increase with travel time, and the...report 1965