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Gill, E.K.A. (author), Akos, D. M. (author)This paper proposes a novel concept of using highly efficient Snapshot Global Navigation Satellite Systems (GNSS) receivers to provide precise position fixes of single or multiple satellites in Low-Earth Orbit (LEO) to improve upper atmospheric modeling and thus contribute to superior space situational awareness (SSA). While tracking of LEO...journal article 2024
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Reis, Rui A. (author), Fortes, Conceição J.E.M. (author), Rodrigues, José A. (author), Hu, Zhan (author), Suzuki, T. (author)Laboratory experiments of wave propagation over rigid and flexible vegetation fields, with the same configurations, were conducted to understand the effect of vegetation flexibility on the drag coefficient (C<sub>D</sub>). The direct method and the least squares method (LSM), based on force and flow measurements, are applied to calculate the...journal article 2024
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Vilumbrales-Garcia, Rodrigo (author), Kurt, Melike (author), Weymouth, Gabriel D. (author), Ganapathisubramani, Bharathram (author)The hydrodynamic influence of surface texture on static surfaces ranges from large drag penalties (roughness) to potential performance benefits (shark-like skin). Although it is of wide-ranging research interest, the impact of roughness on flapping systems has received limited attention. In this work, we explore the effect of roughness on the...journal article 2024
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- Ruland, Oscar (author), Mkhoyan, T. (author), De Breuker, R. (author), Wang, Xuerui (author) journal article 2023
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Abraham Mathews, J. (author), Farahani, H. (author), Sietsma, J. (author), Petrov, R.H. (author), Mecozzi, M.G. (author), Santofimia, Maria Jesus (author)The influence of carbon concentration variations on pearlite formation (20 h at 600 °C) in a case-carburized steel is investigated. The resultant microstructure shows three distinct regions: carburized case, a transition region, and the original core. The microstructural transition from the case to the core regions is observed to be...journal article 2023
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Otori, Hiromasa (author), Kikuchi, Yuka (author), Rivera Arreba, I. (author), Viré, A.C. (author)The hydrodynamic coefficients are evaluated by fully nonlinear Navier-Stokes forced oscillation simulations using the volume of fluid method. Richardson extrapolation is employed to obtain the grid-independent solution. The predicted hydrodynamic coefficients are validated by the water tank tests. The applicability of the drag coefficient...journal article 2023
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Basu, S. (author)In this chapter, we elaborate on several similarity theory-based and empirical wind speed profile formulations. We highlight their strengths and weaknesses through various examples from the literature. Some of these formulations are sometimes inappropriately used in various practical applications (e.g., offshore wind resource assessments). We...book chapter 2023
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van Campenhout, O.W.G. (author), van Nesselrooij, M. (author), Lin, Y. (author), Casacuberta Puig, J. (author), van Oudheusden, B.W. (author), Hickel, S. (author)Although several previous studies have reported a potential drag-reducing effect of dimpled surfaces in turbulent boundary layers, there is a lack of replicability across experiments performed by different research groups. To contribute to the dialogue, we scrutinize one of the most studied dimple geometries reported in the literature, which...journal article 2023
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Jux, C. (author), Sciacchitano, A. (author), Scarano, F. (author)The aerodynamic characteristics of a modern road cycling wheel in cross wind are studied through force- and planar PIV measurements in the TU Delft Open Jet Facility. The performance of the 62 mm deep rim is evaluated for three tire profiles, and yaw angles up to 24°. All measurements are executed at 12.5 m/s (45 km/h) freestream- and wheel...journal article 2023
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Zhang, R. (author), Chen, Y. (author), Lei, Jiaxin (author), Zhou, Xin (author), Yao, P. (author), Stive, M.J.F. (author)Mangroves can function as a ‘bio-shield’ to protect coastal communities from harsh environments because of their strong ability to attenuate wave energy. However, as mangroves are usually oversimplified as rigid cylinders in antecedent studies, the effects of complex mangrove morphology on wave attenuation have not been well researched....journal article 2023
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ten Bosch, B.I.M. (author)A variational principle for the Upper Convected Maxwell model is presented. The stationary value of the appropriate functional is the drag on an immersed object. From the principle, a formula is derived for the derivative of the drag with respect to the Deborah number for an arbitrarily shaped particle in a circular duct under creeping flow...journal article 2023
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El Hasadi, Yousef M.F. (author), Padding, J.T. (author)At the beginning of the second half of the twentieth century, Proudman and Pearson (J. Fluid. Mech.,2(3), 1956, pp.237–262) suggested that the functional form of the drag coefficient (C<sub>D</sub>) of a single sphere subjected to uniform fluid flow consists of a series of logarithmic and power terms of the Reynolds number (Re). In this paper...journal article 2023
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Carrasco Grau, J. (author), van Campenhout, O.W.G. (author), Hartog, F.H. (author), van Nesselrooij, M. (author), Baars, W.J. (author), Schrijer, F.F.J. (author)Chevron-shaped protrusions have been proposed in the literature for turbulent skin friction reduction. However, there is no consensus on the performance of this passive flow control technique; both an increase and a decrease in drag have been observed in previous studies. There is also no experimental evidence to support the working mechanism...journal article 2023
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Lin, J. (author)Estuaries are the core area of land-sea interactions and have significant ecological and economic value. In estuaries, hydrodynamics and sediment dynamics are the crucial processes governing geomorphology, navigability, and primary production. Since the turn of the 20th century, increased human activities (e.g., damming, dredging, and...doctoral thesis 2022
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Spoelstra, A.M.C.M.G. (author)The research presented in this thesis introduces a new measurement concept for on-site aerodynamic measurements based on large-scale stereoscopic particle image velocimetry (stereo-PIV) measurements past an athlete, a vehicle or an object travelling through a quiescent environment. The analysis of the momentumdeficit past the transit poses the...doctoral thesis 2022
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Smith, Lloyd (author), Sciacchitano, A. (author)While baseball is a popular sport with a storied history, the aerodynamic properties of the seamed sports ball are not fully understood. Reported aerodynamic baseball behaviors are primarily based on force measurements from wind tunnels. The following describes a methodology to measure baseball drag in free flight from changes in its speed. The...journal article 2022
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Lovato, S. (author), Toxopeus, S.L. (author), Settels, J.W. (author), Keetels, G.H. (author)The ship’s resistance and manoeuvrability in shallow waters can be adversely influenced by the presence of fluid mud layers on the seabed of ports and waterways. Fluid mud exhibits a complex non-Newtonian rheology that is often described using the Herschel–Bulkley model. The latter has been recently implemented in a maritime finite-volume CFD...journal article 2022
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Bruinsma, Sean (author), Siemes, C. (author), Emmert, John T. (author), Mlynczak, Martin G. (author)The quality and distribution in time and space of available atmospheric observations are crucial for the accuracy of semi-empirical thermosphere models. However, datasets can be inconsistent, and their qualities and resolutions are often unequal. The main thermospheric density datasets of this century are briefly described and then compared...journal article 2022
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Sanjeevi, Sathish K.P. (author), Dietiker, Jean F. (author), Padding, J.T. (author)Detailed simulations of flow around various prolate spheroids are performed using multi-relaxation time lattice Boltzmann method (LBM). The simulations are performed in the Reynolds numbers range 0.1≤Re≤2000 at different incident angles 0<sup>∘</sup>≤ϕ≤90<sup>∘</sup> for various prolate spheroids of aspect ratios 1≤λ≤8. The Re is based on the...journal article 2022
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Hu, Z. (author), Lian, S. (author), Zitman, T.J. (author), Wang, H. (author), He, Z. (author), Wei, H. (author), Ren, L. (author), Uijttewaal, W.S.J. (author), Suzuki, T. (author)Wave height attenuation in vegetation canopies is often all attributed to the drag force exerted by vegetation, whereas other potential dissipation process is often neglected. Previous studies without vegetation have found that opposing currents can induce wave breaking and greatly increase dissipation. It is not clear if similar process may...journal article 2022