Searched for: subject%3A%22Length%255C+scale%22
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Basu, S. (author), Holtslag, Albert A.M. (author)
In this paper, we revisit a well-known formulation of temperature structure parameter (CT2), originally proposed by V. I. Tatarskii. We point out its limitations and propose a revised formulation based on turbulence variance and flux budget equations. Our formulation includes a novel physically-based outer length scale which can be estimated...
journal article 2022
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Ponnusami, Sathiskumar Anusuya (author), Krishnasamy, J. (author), Turteltaub, S.R. (author), van der Zwaag, S. (author)
The influence of the cohesive zone length on the crack driving force is quantified and analyzed in a representative system of particles dispersed in a matrix of a composite material. For heterogeneous material systems, e.g. particulate composites, it is known that as a crack approaches the particles, the crack driving force may increase ...
journal article 2022
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Basu, S. (author), Holtslag, Albert A.M. (author)
In this study, the stability dependence of turbulent Prandtl number (Pr<sub>t</sub>) is quantified via a novel and simple analytical approach. Based on the variance and flux budget equations, a hybrid length scale formulation is first proposed and its functional relationships to well-known length scales are established. Next, the ratios of...
journal article 2021
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Poppema, Daan W. (author), Wijnberg, Kathelijne M. (author), Mulder, Jan P.M. (author), Vos, S.E. (author), Hulscher, Suzanne J.M.H. (author)
In sandy environments, like the beach-dune system, buildings not only affect the airflow, but also the aeolian sediment transport in their surroundings. In this study, we determine how the horizontal size of sediment deposition patterns around buildings depends on the building's dimensions. Four one-day experiments were conducted at the beach...
journal article 2021
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Dai, Yi (author)
In current study, several fundamental and inherent problems in original Deardorff subgrid model are identified under stably stratified condition. It is found that the mixing length parameterization in this subgrid model is at the root of a long trouble problem of grid size sensitivity in large-eddy simulation (LES). A new formulation of mixing...
master thesis 2020
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Basu, S. (author), He, Ping (author), DeMarco, Adam W. (author)
We use a database of direct numerical simulations to evaluate parametrizations for energy dissipation rate in stably stratified flows. We show that shear-based formulations are more appropriate for stable boundary layers than commonly used buoyancy-based formulations. As part of the derivations, we explore several length scales of turbulence...
journal article 2020
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Basu, S. (author), DeMarco, Adam W. (author), He, Ping (author)
In this study, we explore several integral and outer length scales of turbulence which can be formulated by using the dissipation of temperature fluctuations (χ) and other relevant variables. Our analyses directly lead to simple yet non-trivial parameterizations for both spatially-averaged χ¯ and the structure parameter of temperature (CT2)....
journal article 2020
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Dai, Y. (author), Basu, S. (author), Maronga, Björn (author), de Roode, S.R. (author)
We have identified certain fundamental limitations of a mixing-length parametrization used in a popular turbulent kinetic energy-based subgrid-scale model. Replacing this parametrization with a more physically realistic one significantly improves the overall quality of the large-eddy simulation (LES) of stable boundary layers. For the range...
journal article 2020
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Edens, Maike (author)
The fracture properties of natural materials often outperform artificial material properties. This could be explained by their complex multi-scale (anisotropic) hard-soft material structure, starting at a nano-scale. The interest in the fabrication of complex biomimetic hard-soft materials and interfaces is growing due to their high fracture...
master thesis 2018
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Vandoren, B.S.L. (author), Simone, A. (author)
Two anisotropic stress-based gradient-enhanced damage models are proposed to address the issue of spurious damage growth typical of continuous standard gradient-enhanced damage models. Both models are based on a decreasing interaction length upon decreasing stresses and do not require additional model parameters or extra degrees of freedom...
journal article 2018
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Zhang, H. (author), Šavija, B. (author), Xu, Y. (author), Schlangen, E. (author)
Cement paste possesses complex microstructural features including defects/pores over a range of length-scales, from nanometres to millimetres in size. As a consequence, it exhibits different behaviour under loading depending on the size. In this work, cubic specimens in a size range of 1: 400 were produced and tested by a one-sided splitting...
journal article 2018
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Iacono, C. (author)
In the last years, many computational models have been developed for tensile fracture in concrete. However, their reliability is related to the correct estimate of the model parameters, not all directly measurable during laboratory tests. Hence, the development of inverse procedures is needed, that provides the parameters estimate minimizing,...
doctoral thesis 2007
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Peng, S.H. (author)
A detached eddy simulation modelling approach is presented for turbulent flow computations, which is based on the transport equation for turbulent kinetic energy, k (and thus termed k-DES model). The model coefficients in the RANS form are calibrated in wall-attached flow computations, and the LES mode is calibrated in the simulation for...
conference paper 2006
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Davidson, L. (author)
The SAS model (Scale Adapted Simulation) was invented by Menter and co-workers. The idea behind the SST-SAS k-omega model is to add an additional production term -- the SAS term -- in the omega equation, which is sensitive to resolved (i.e. unsteady) fluctuations. When the flow equations resolve turbulence, the length scale based on velocity...
conference paper 2006
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Wang, W.M. (author), Sluys, L.J. (author), De Borst, R. (author)
journal article 1997
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Carmeliet, J. (author), De Borst, R. (author)
journal article 1995
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De Borst, R. (author), Sluys, L.J. (author), Muhlhaus, H.B. (author), Pamin, J. (author)
journal article 1993
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De Borst, R. (author)
journal article 1993
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Sluys, L.J. (author), De Borst, R. (author), Muhlhaus, H.B. (author)
journal article 1993
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Sluys, L.J. (author), De Borst, R. (author)
journal article 1992
Searched for: subject%3A%22Length%255C+scale%22
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