Article
Oceanography
Dong Wang, Tobias Kukulka
Summary: This study investigates the dynamics of velocity shear and Reynolds stress in the ocean surface boundary layer for idealized misaligned wind and wave fields using a large-eddy simulation (LES) model. The results suggest that the misalignment between Reynolds stress and Eulerian shear may have an impact on driving upper-ocean currents and accurate turbulence parameterizations in misaligned wind-wave conditions.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2021)
Article
Mechanics
H. Sadeghi, M. Oberlack, M. Gauding
Summary: This study derives new scaling laws for passive scalar statistical quantities in temporally and spatially evolving plane turbulent jet flows using Lie symmetry analysis, filling the gaps in classical self-similarity analysis. The newly derived scaling laws exhibit self-similarity up to the third moments, in contrast to classical laws which primarily show self-similarity for the first moments.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Multidisciplinary
P. Morel, Shaokang Xu, O. D. Gurcan
Summary: The study of two-dimensional passive scalar turbulence using a k-space diffusion model based on a third order differential approximation provides general expressions for local nonlinear interactions in Fourier space. The steady state solutions recover Kraichnan-Kolmogorov phenomenology and various passive scalar spectra. Numerical solutions confirm the analytical results for energy and passive scalar injections and dissipations over a wide range of scales.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2021)
Article
Meteorology & Atmospheric Sciences
Yanle Lu, Luca Delle Monache, Jeffrey Weil, Keith Ngan, Qi Li
Summary: Using obstacle-resolving large-eddy simulations (LES), this study investigates the impact of urban roughness on the predictability of passive scalar dispersion. The results show that urban roughness decreases the predictability of the passive scalar and disrupts the similarity between the error statistics of the velocity and the passive scalar.
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2023)
Article
Meteorology & Atmospheric Sciences
Dongxiao Wang, Guojing Li, Lian Shen, Yeqiang Shu
Summary: Langmuir turbulence is a complex turbulent process in the ocean upper mixed layer. This study investigates the impact of the Coriolis parameter on Langmuir turbulence at different latitudes using a simulation model. The findings suggest that the Coriolis parameter has a significant modulation effect on the mean and turbulent statistics of Langmuir turbulence, with RME = 0.266 (LAT = 50 degrees N) being a key value for this effect.
ADVANCES IN ATMOSPHERIC SCIENCES
(2022)
Article
Computer Science, Interdisciplinary Applications
Shujaut H. Bader, Zifei Yin, Paul A. Durbin
Summary: This paper reproduces an experiment conducted by Blair (1983) on flat plate transition under freestream turbulence with heat transfer using subgrid dynamic scalar-flux models. An improved Higher Order Generalized Gradient Diffusion Hypothesis (HOGGDH) model is proposed with a modified, spatially varying model coefficient based on observations to increase accuracy near the wall. The improved version of the HOGGDH model shows accurate predictions of mean temperature and scalar flux compared to other models.
COMPUTERS & FLUIDS
(2022)
Article
Computer Science, Interdisciplinary Applications
L. Engelmann, J. Hasslberger, E. Inanc, M. Klein, A. Kempf
Summary: This study investigates the impact of the choice of the subgrid-model on the simulation results of reactive flows in LES. By comparing the simulations with flame-resolved results, it is found that the regularized scale-similarity-type model and the sensor-enhanced Smagorinsky model can achieve satisfactory simulation results while maintaining stability.
COMPUTERS & FLUIDS
(2022)
Article
Engineering, Chemical
Nima Fallah Jouybari, T. Staffan Lundstroem
Summary: Large eddy simulations were conducted in a channel partially filled with spherical particles to investigate the effect of turbulence mixing and channeling effect on passive scalar transport from the channel wall. It was found that the distance between particles, particle diameter, and gap thickness play important roles in influencing passive scalar transport. The channeling effect was identified as the most significant parameter affecting the scalar transport rate in the study.
Article
Meteorology & Atmospheric Sciences
Ali Khosronejad, Ajay B. B. Limaye, Zexia Zhang, Seokkoo Kang, Xiaolei Yang, Fotis Sotiropoulos
Summary: The interaction between flow, sediment transport, and bed topography plays a crucial role in the formation of bedforms and channel migration in meandering rivers. Predicting these interactions is vital for river engineering and geoscience research. Researchers conducted simulations to study the morphodynamics and bed deformation in 42 meandering rivers with different planform shapes. The simulations revealed the formation of scour and deposition patterns near the outer and inner banks and the variation of point bars and scour regions around the meander bends.
JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS
(2023)
Article
Mechanics
Mengyuan Yuan, Hengbin Zhang, Chenning Tong
Summary: Research on the scalar-scalar-gradient filtered joint density function (FJDF) for turbulent combustion large eddy simulation reveals that the FJDF is unimodal when the subgrid-scale (SGS) scalar variance is small compared to its mean value, and the scalar gradient weakly depends on the SGS scalar under such conditions.
Article
Multidisciplinary Sciences
Floriane Sudre, Ismael Hernandez-Carrasco, Camille Mazoyer, Joel Sudre, Boris Dewitte, Veronique Garcon, Vincent Rossi
Summary: Fronts are important features in the global ocean, contributing to enhanced vertical velocities and primary production. Studying front-marine life interactions is crucial for resource management and spatial planning. The Mediterranean Sea and the Southwest Indian Ocean provide ideal conditions for studying these interactions. By combining thermal fronts and attracting Lagrangian coherent structures, a high-resolution front dataset with long time coverage can be obtained.
Article
Oceanography
Xingchi Wang, Tobias Kukulka
Summary: The study investigates the impact of turbulence driven by wind and waves on the transport of heat, momentum, and matter in the ocean surface boundary layer (OSBL). The experiments reveal a three-stage response of the OSBL to abrupt changes in wind direction, with different characteristics such as decreased turbulent kinetic energy (TKE), increased TKE, and eventual relaxation to equilibrium, while Langmuir turbulence (LT) continues to adjust due to slowly developing waves.
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2021)
Article
Chemistry, Multidisciplinary
Soizic Esnault, Florent Duchaine, Laurent Y. M. Gicquel, Stephane Moreau
Summary: This study uses Large-Eddy Simulations to evaluate the flow dynamics and heat transfer mechanisms in acoustic liners of aircraft fan ducts. Two configurations are considered: a lab-scale one for validation and an engine-scale one for practical application. The simulations show that synthetic jets fully drive the flow dynamics in the jet wakes, and upstream turbulence affects the development of the jet rows and wall heat transfer between jets.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Mechanical
Peng Huang, Kuanyu Chen, Huaiwu Peng, Hsu-Chew Lee, Yipeng Shi, Zuoli Xiao, Shiyi Chen, Minping Wan
Summary: In this paper, a constrained large-eddy simulation (C-LES) model is developed for simulating passive scalar in turbulent flows. The model calculates the coefficients of the dynamic mixed nonlinear model (MNLM) by imposing a physical constraint based on the scale-invariance of the scalar variance flux in the large-eddy simulation (LES) of passive scalar. The model is compared with different subgrid-scale (SGS) models and filtered direct numerical simulation (fDNS) results, showing superior performance in predicting the SGS scalar flux and scalar spectrum evolution.
ACTA MECHANICA SINICA
(2023)
Article
Mathematics, Applied
Arnaud Debussche, Berenger Hug, Etienne Memin
Summary: In this paper, the theoretical properties of a stochastic representation of the incompressible Navier-Stokes equations under location uncertainty (LU) are analyzed. This framework incorporates a transport noise, large scale diffusion term, and a modified advection term. The existence of martingale solutions for the stochastic Navier-Stokes equations in LU form is demonstrated, as well as their uniqueness for 2D flows. It is also proved that as the noise intensity tends to zero, these solutions converge to a solution of the deterministic Navier-Stokes equation in dimension 3.
JOURNAL OF MATHEMATICAL FLUID MECHANICS
(2023)
Article
Oceanography
Nityanand Sinha, Andres E. Tejada-Martinez, Cigdem Akan, Chester E. Grosch
JOURNAL OF PHYSICAL OCEANOGRAPHY
(2015)
Article
Oceanography
Cigdem Akan, Saeed Moghimi, H. Tuba Ozkan-Haller, John Osborne, Alexander Kurapov
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2017)
Article
Oceanography
Robyn L. Smyth, Cigdem Akan, Andres Tejada-Martinez, Patrick J. Neale
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2017)
Article
Oceanography
Yusuke Uchiyama, James C. McWilliams, Cigdem Akan
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2017)
Article
Mechanics
James C. McWilliams, Cigdem Akan, Yusuke Uchiyama
JOURNAL OF FLUID MECHANICS
(2018)
Article
Meteorology & Atmospheric Sciences
Cigdem Akan, James C. McWilliams, Saeed Moghimi, H. Tuba Oezkan-Haller
Article
Thermodynamics
Guillaume Martinat, Chester E. Grosch, Thomas B. Gatski
FLOW TURBULENCE AND COMBUSTION
(2014)
Article
Thermodynamics
R. Walker, A. E. Tejada-Martinez, G. Martinat, C. E. Grosch
INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW
(2014)
Article
Physics, Multidisciplinary
Andres E. Tejada-Martinez, Cigdem Akan, Nityanand Sinha, Chester E. Grosch, Guillaume Martinat
Article
Meteorology & Atmospheric Sciences
Saeed Moghimi, H. Tuba Ozkan-Haller, Cigdem Akan, Joseph T. Jurisa
Article
Mechanics
A. E. Tejada-Martinez, A. Hafsi, C. Akan, M. Juha, F. Veron
JOURNAL OF FLUID MECHANICS
(2020)
Article
Meteorology & Atmospheric Sciences
Cigdem Akan, James C. McWilliams, Yusuke Uchiyama
Article
Oceanography
Alyssa M. LeClaire, Eric N. Powell, Roger Mann, Kathleen M. Hemeon, Sara M. Pace, Vincent Saba, Hubert du Pontavice, Jillian R. Sower
Summary: Arctica islandica is an important species for recording climate change on the U.S. northeast continental shelf, and its growth rates show synchronous changes with cold and warm climatic periods. This study finds that A. islandica near the Delmarva Peninsula had higher growth rates during cold periods, possibly due to increased food supply in shallower water. The range recession of this species is a long-term process determined by the survivorship of older individuals.
CONTINENTAL SHELF RESEARCH
(2024)