Log in

Relevant bibliographies by topics / Subgrid / Journal articles

To see the other types of publications on this topic, follow the link: Subgrid.

Journal articles on the topic 'Subgrid'

Author: Grafiati

Published: 4 June 2021

Last updated: 19 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Subgrid.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

NESLITURK, ALI I. "A STABILIZING SUBGRID FOR CONVECTION–DIFFUSION PROBLEM." Mathematical Models and Methods in Applied Sciences 16, no. 02 (February 2006): 211–31. http://dx.doi.org/10.1142/s0218202506001121.

Full text

Abstract:

A stabilizing subgrid which consists of a single additional node in each triangular element is analyzed by solving the convection–diffusion problem, especially in the case of small diffusion. The choice of the location of the subgrid node is based on minimizing the residual of a local problem inside each element. We study convergence properties of the method under consideration and its connection with previously suggested stabilizing subgrids. We prove that the standard Galerkin finite element solution on augmented grid produces a discrete solution that satisfy the same a priori error estimate

APA, Harvard, Vancouver, ISO, and other styles

2

Yeh, Pat J.-F., and Elfatih A. B. Eltahir. "Representation of Water Table Dynamics in a Land Surface Scheme. Part II: Subgrid Variability." Journal of Climate 18, no. 12 (June 15, 2005): 1881–901. http://dx.doi.org/10.1175/jcli3331.1.

Full text

Abstract:

Abstract A lumped unconfined aquifer model has been developed and interactively coupled to a land surface scheme in a companion paper. Here, the issue of the representation of subgrid variability of water table depths (WTDs) is addressed. A statistical–dynamical (SD) approach is used to account for the effects of the unresolved subgrid variability of WTD in the grid-scale groundwater runoff. The dynamic probability distribution function (PDF) of WTD is specified as a two-parameter gamma distribution based on observations. The grid-scale groundwater rating curve (i.e., aquifer storage–discharge

APA, Harvard, Vancouver, ISO, and other styles

3

Habets, F., and G. M. Saulnier. "Subgrid runoff parameterization." Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere 26, no. 5-6 (January 2001): 455–59. http://dx.doi.org/10.1016/s1464-1909(01)00034-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Valdettaro, L. "Subgrid-Scale modeling." EAS Publications Series 21 (2006): 197–218. http://dx.doi.org/10.1051/eas:2006114.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Park, Noma, and Krishnan Mahesh. "A velocity-estimation subgrid model constrained by subgrid scale dissipation." Journal of Computational Physics 227, no. 8 (April 2008): 4190–206. http://dx.doi.org/10.1016/j.jcp.2007.12.020.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Chen, Yaling, Luxi Hao, and Gaowen Yin. "Distributed Energy Management of the Hybrid AC/DC Microgrid with High Penetration of Distributed Energy Resources Based on ADMM." Complexity 2021 (September 14, 2021): 1–9. http://dx.doi.org/10.1155/2021/1863855.

Full text

Abstract:

This paper aims to investigate energy management of the hybrid AC/DC microgrid with the high penetration of distributed energy resources (DERs), such as electrical vehicles, heat pumps, and photovoltaics. In the previous studies, energy management of the hybrid microgrid is usually carried out by the system operator in a centralized manner, which suffers from the compromise of privacy information protection and the risk of single-point failure. Therefore, this paper proposes a distributed energy management scheme of the hybrid microgrid using the projection function-based alternating direction

APA, Harvard, Vancouver, ISO, and other styles

7

Zhou, Ye. "Eddy damping, backscatter, and subgrid stresses in subgrid modeling of turbulence." Physical Review A 43, no. 12 (June 1, 1991): 7049–52. http://dx.doi.org/10.1103/physreva.43.7049.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Brillant, Guillaume, Sabine Husson, and Françoise Bataille. "Subgrid-Scale Diffusivity: Wall Behavior and Dynamic Methods." Journal of Applied Mechanics 73, no. 3 (September 26, 2004): 360–67. http://dx.doi.org/10.1115/1.2173005.

Full text

Abstract:

This study concerns the near-wall behavior of the subgrid-scale diffusivity. This is shown to depend on the thermal boundary conditions. Therefore, the constant subgrid-scale Prandtl number hypothesis is questionable and a direct modeling of the subgrid-scale diffusivity is considered instead. Large-eddy simulations are carried out using the Trio U code in a turbulent channel flow configuration with the three classical thermal boundary conditions (constant temperature, constant heat flux, and adiabatic wall). Different dynamic methods are used to model the subgrid-scale diffusivity and results

APA, Harvard, Vancouver, ISO, and other styles

9

Kitsios, Vassili, Jorgen S. Frederiksen, and Meelis J. Zidikheri. "Subgrid Model with Scaling Laws for Atmospheric Simulations." Journal of the Atmospheric Sciences 69, no. 4 (March 30, 2012): 1427–45. http://dx.doi.org/10.1175/jas-d-11-0163.1.

Full text

Abstract:

Abstract Subgrid-scale parameterizations with self-similar scaling laws are developed for large-eddy simulations (LESs) of atmospheric flows. The key new contribution is the development of scaling laws that govern how these parameterizations depend on the LES resolution and flow strength. Both stochastic and deterministic representations of the effects of subgrid-scale eddies on the retained scales are considered. The stochastic subgrid model consists of a backscatter noise term and a drain eddy viscosity, while in the deterministic subgrid model the net effect of these two terms is represente

APA, Harvard, Vancouver, ISO, and other styles

10

Verrelle, Antoine, Didier Ricard, and Christine Lac. "Evaluation and Improvement of Turbulence Parameterization inside Deep Convective Clouds at Kilometer-Scale Resolution." Monthly Weather Review 145, no. 10 (October 2017): 3947–67. http://dx.doi.org/10.1175/mwr-d-16-0404.1.

Full text

Abstract:

A challenge for cloud-resolving models is to make subgrid schemes suitable for deep convective clouds. A benchmark large-eddy simulation (LES) was conducted on a deep convective cloud with 50-m grid spacing. The reference turbulence fields for horizontal grid spacings of 500 m, 1 km, and 2 km were deduced by coarse graining the 50-m LES outputs, allowing subgrid fields to be characterized. The highest values of reference subgrid turbulent kinetic energy (TKE) were localized in the updraft core, and the production of subgrid TKE was dominated by thermal effects at coarser resolution (2 and 1 km

APA, Harvard, Vancouver, ISO, and other styles

11

Meneveau, Charles. "Turbulence: Subgrid-Scale Modeling." Scholarpedia 5, no. 1 (2010): 9489. http://dx.doi.org/10.4249/scholarpedia.9489.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Sagaut, P., P. Comte, and F. Ducros. "Filtered subgrid-scale models." Physics of Fluids 12, no. 1 (January 2000): 233–36. http://dx.doi.org/10.1063/1.870297.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Vinuesa, Jean-François, and Fernando Porté-Agel. "Dynamic Models for the Subgrid-Scale Mixing of Reactants in Atmospheric Turbulent Reacting Flows." Journal of the Atmospheric Sciences 65, no. 5 (May 1, 2008): 1692–99. http://dx.doi.org/10.1175/2007jas2392.1.

Full text

Abstract:

Abstract The effects of the subgrid scales on chemical transformations in large-eddy simulations of the convective atmospheric boundary layer (CBL) are investigated. Dynamic similarity subgrid-scale models are formulated and used to calculate the subgrid-scale covariance. The dynamic procedure allows for simulations free of parameter tuning since the model coefficients are computed based on the resolved reactant concentrations. A scale-dependent procedure is proposed that allows relaxing the assumption of scale invariance used in the dynamic similarity model. Simulation results show that both

APA, Harvard, Vancouver, ISO, and other styles

14

Tesfa, Teklu K., and Lai-Yung Ruby Leung. "Exploring new topography-based subgrid spatial structures for improving land surface modeling." Geoscientific Model Development 10, no. 2 (February 22, 2017): 873–88. http://dx.doi.org/10.5194/gmd-10-873-2017.

Full text

Abstract:

Abstract. Topography plays an important role in land surface processes through its influence on atmospheric forcing, soil and vegetation properties, and river network topology and drainage area. Land surface models with a spatial structure that captures spatial heterogeneity, which is directly affected by topography, may improve the representation of land surface processes. Previous studies found that land surface modeling, using subbasins instead of structured grids as computational units, improves the scalability of simulated runoff and streamflow processes. In this study, new land surface s

APA, Harvard, Vancouver, ISO, and other styles

15

Ke, Y., L. R. Leung, M. Huang, and H. Li. "Enhancing the representation of subgrid land surface characteristics in land surface models." Geoscientific Model Development 6, no. 5 (September 27, 2013): 1609–22. http://dx.doi.org/10.5194/gmd-6-1609-2013.

Full text

Abstract:

Abstract. Land surface heterogeneity has long been recognized as important to represent in the land surface models. In most existing land surface models, the spatial variability of surface cover is represented as subgrid composition of multiple surface cover types, although subgrid topography also has major controls on surface processes. In this study, we developed a new subgrid classification method (SGC) that accounts for variability of both topography and vegetation cover. Each model grid cell was represented with a variable number of elevation classes and each elevation class was further d

APA, Harvard, Vancouver, ISO, and other styles

16

Erlebacher, G., M. Y. Hussaini, C. G. Speziale, and T. A. Zang. "Toward the large-eddy simulation of compressible turbulent flows." Journal of Fluid Mechanics 238 (May 1992): 155–85. http://dx.doi.org/10.1017/s0022112092001678.

Full text

Abstract:

New subgrid-scale models for the large-eddy simulation of compressible turbulent flows are developed and tested based on the Favre-filtered equations of motion for an ideal gas. A compressible generalization of the linear combination of the Smagorinsky model and scale-similarity model, in terms of Favre-filtered fields, is obtained for the subgrid-scale stress tensor. An analogous thermal linear combination model is also developed for the subgrid-scale heat flux vector. The two dimensionless constants associated with these subgrid-scale models are obtained by correlating with the results of di

APA, Harvard, Vancouver, ISO, and other styles

17

Zidikheri, Meelis J., and Jorgen S. Frederiksen. "Stochastic subgrid-scale modelling for non-equilibrium geophysical flows." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 368, no. 1910 (January 13, 2010): 145–60. http://dx.doi.org/10.1098/rsta.2009.0192.

Full text

Abstract:

Methods motivated by non-equilibrium statistical mechanics of turbulence are applied to solve an important practical problem in geophysical fluid dynamics, namely the parametrization of subgrid-scale eddies needed in large-eddy simulations (LESs). A direct stochastic modelling scheme that is closely related to techniques based on statistical closure theories, but which is more generally applicable to complex models, is employed. Here, we parametrize the effects of baroclinically unstable subgrid-scale eddies in idealized flows with broad similarities to the Antarctic Circumpolar Current of the

APA, Harvard, Vancouver, ISO, and other styles

18

Moser, Robert D., Sigfried W. Haering, and Gopal R. Yalla. "Statistical Properties of Subgrid-Scale Turbulence Models." Annual Review of Fluid Mechanics 53, no. 1 (January 5, 2021): 255–86. http://dx.doi.org/10.1146/annurev-fluid-060420-023735.

Full text

Abstract:

This review examines large eddy simulation (LES) models from the perspective of their a priori statistical characteristics. The most well-known statistical characteristic of an LES subgrid-scale model is its dissipation (energy transfer to unresolved scales), and many models are directly or indirectly formulated and tuned for consistency of this characteristic. However, in complex turbulent flows, many other subgrid statistical characteristics are important. These include such quantities as mean subgrid stress, subgrid transport of resolved Reynolds stress, and dissipation anisotropy. Also imp

APA, Harvard, Vancouver, ISO, and other styles

19

Su, Mingde, Qingyan Chen, and Che-Ming Chiang. "Comparison of Different Subgrid-Scale Models of Large Eddy Simulation for Indoor Airflow Modeling." Journal of Fluids Engineering 123, no. 3 (March 15, 2001): 628–39. http://dx.doi.org/10.1115/1.1378294.

Full text

Abstract:

The Smagorinsky subgrid-scale model, a dynamic subgrid-scale model, and a stimulated subgrid-scale model have been used in a large eddy simulation (LES) program to compute airflow in a room. A fast Fourier transformation (FFT) method and a conventional iteration method were used in solving the Poisson equation. The predicted distributions of indoor air velocity, temperature, and contaminant concentrations show that the three subgrid-scale models can produce acceptable results for indoor environment design. The dynamic and stimulated models performed slightly better than the Smagorinsky model.

APA, Harvard, Vancouver, ISO, and other styles

20

Honnert, Rachel, Valéry Masson, and Fleur Couvreux. "A Diagnostic for Evaluating the Representation of Turbulence in Atmospheric Models at the Kilometric Scale." Journal of the Atmospheric Sciences 68, no. 12 (December 1, 2011): 3112–31. http://dx.doi.org/10.1175/jas-d-11-061.1.

Full text

Abstract:

Abstract Turbulence is well represented by atmospheric models at very fine grid sizes, from 10 to 100 m, for which turbulent movements are mainly resolved, and by atmospheric models with grid sizes greater than 2 km, for which those movements are entirely parameterized. But what happens at intermediate scales, Wyngaard’s so-called terra incognita? Here an original method is presented that provides a new diagnostic by calculating the subgrid and resolved parts of five variables at different scales: turbulent kinetic energy (TKE), heat and moisture fluxes, and potential temperature and mixing ra

APA, Harvard, Vancouver, ISO, and other styles

21

Tonttila, J., P. Räisänen, and H. Järvinen. "Monte Carlo-based subgrid parameterization of vertical velocity and stratiform cloud microphysics in ECHAM5.5-HAM2." Atmospheric Chemistry and Physics Discussions 13, no. 2 (February 27, 2013): 5477–507. http://dx.doi.org/10.5194/acpd-13-5477-2013.

Full text

Abstract:

Abstract. A new method for parameterizing the subgrid variations of vertical velocity and cloud droplet number concentration (CDNC) is presented for GCMs. These parameterizations build on top of existing parameterizations that create stochastic subgrid cloud columns inside the GCM grid-cells, which can be employed by the Monte Carlo independent column approximation approach for radiative transfer. The new model version adds a description for vertical velocity in individual subgrid columns, which can be used to compute cloud activation and the subgrid distribution of the number of cloud droplet

APA, Harvard, Vancouver, ISO, and other styles

22

Zhang, Xu, Jian-Wen Bao, Baode Chen, and Evelyn D. Grell. "A Three-Dimensional Scale-Adaptive Turbulent Kinetic Energy Scheme in the WRF-ARW Model." Monthly Weather Review 146, no. 7 (July 2018): 2023–45. http://dx.doi.org/10.1175/mwr-d-17-0356.1.

Full text

Abstract:

A new three-dimensional (3D) turbulent kinetic energy (TKE) subgrid mixing scheme is developed using the Advanced Research version of the Weather Research and Forecasting (WRF) Model (WRF-ARW) to address the gray-zone problem in the parameterization of subgrid turbulent mixing. The new scheme combines the horizontal and vertical subgrid turbulent mixing into a single energetically consistent framework, in contrast to the conventionally separate treatment of the vertical and horizontal mixing. The new scheme is self-adaptive to the grid-size change between the large-eddy simulation (LES) and me

APA, Harvard, Vancouver, ISO, and other styles

23

Im, E.-S., E. Coppola, F. Giorgi, and X. Bi. "Validation of a High-Resolution Regional Climate Model for the Alpine Region and Effects of a Subgrid-Scale Topography and Land Use Representation." Journal of Climate 23, no. 7 (April 1, 2010): 1854–73. http://dx.doi.org/10.1175/2009jcli3262.1.

Full text

Abstract:

Abstract A mosaic-type parameterization of subgrid-scale topography and land use (SubBATS) is applied for a high-resolution regional climate simulation over the Alpine region with a regional climate model (RegCM3). The model coarse-gridcell size in the control simulation is 15 km while the subgridcell size is 3 km. The parameterization requires disaggregation of atmospheric variables from the coarse grid to the subgrid and aggregation of surface fluxes from the subgrid to the coarse grid. Two 10-yr simulations (1983–92) are intercompared, one without (CONT) and one with (SUB) the subgrid schem

APA, Harvard, Vancouver, ISO, and other styles

24

Tonttila, J., H. Järvinen, and P. Räisänen. "Explicit representation of subgrid variability in cloud microphysics yields weaker aerosol indirect effect in the ECHAM5-HAM2 climate model." Atmospheric Chemistry and Physics Discussions 14, no. 10 (June 12, 2014): 15523–43. http://dx.doi.org/10.5194/acpd-14-15523-2014.

Full text

Abstract:

Abstract. Impacts of representing cloud microphysical processes in a stochastic subcolumn framework are investigated, with emphasis on estimating the aerosol indirect effect. It is shown that subgrid treatment of cloud activation and autoconversion of cloud water to rain reduce the impact of anthropogenic aerosols on cloud properties and thus reduce the global mean aerosol indirect effect by 18%, from 1.59 to 1.30 W m−2. Although the results show the importance of considering subgrid variability in the treatment of autoconversion, representing several processes in a self-consistent subgrid fra

APA, Harvard, Vancouver, ISO, and other styles

25

Huang, Wei, J. W. Bao, Xu Zhang, and Baode Chen. "Comparison of the Vertical Distributions of Cloud Properties from Idealized Extratropical Deep Convection Simulations Using Various Horizontal Resolutions." Monthly Weather Review 146, no. 3 (March 1, 2018): 833–51. http://dx.doi.org/10.1175/mwr-d-17-0162.1.

Full text

Abstract:

ABSTRACT The authors coarse-grained and analyzed the output from a large-eddy simulation (LES) of an idealized extratropical supercell storm using the Weather Research and Forecasting (WRF) Model with various horizontal resolutions (200 m, 400 m, 1 km, and 3 km). The coarse-grained physical properties of the simulated convection were compared with explicit WRF simulations of the same storm at the same resolution of coarse-graining. The differences between the explicit simulations and the coarse-grained LES output increased as the horizontal grid spacing in the explicit simulation coarsened. Th

APA, Harvard, Vancouver, ISO, and other styles

26

LANGFORD, JACOB A., and ROBERT D. MOSER. "Optimal LES formulations for isotropic turbulence." Journal of Fluid Mechanics 398 (November 10, 1999): 321–46. http://dx.doi.org/10.1017/s0022112099006369.

Full text

Abstract:

It is shown that there is an abstract subgrid model that is in all senses ideal. An LES using the ideal subgrid model will exactly reproduce all single-time, multi-point statistics, and at the same time will have minimum possible error in instantaneous dynamics. The ideal model is written as an average over the real turbulent fields whose large scales match the current LES field. But this conditional average cannot be computed directly. Rather, the ideal model is the target for approximation when developing practical models, though no new practical models are presented here. To construct such

APA, Harvard, Vancouver, ISO, and other styles

27

Yano, J. I. "Mass-flux subgrid-scale parameterization in analogy with multi-component flows: a formulation towards scale independence." Geoscientific Model Development 5, no. 6 (November 21, 2012): 1425–40. http://dx.doi.org/10.5194/gmd-5-1425-2012.

Full text

Abstract:

Abstract. A generalized mass-flux formulation is presented, which no longer takes a limit of vanishing fractional areas for subgrid-scale components. The presented formulation is applicable to a~situation in which the scale separation is still satisfied, but fractional areas occupied by individual subgrid-scale components are no longer small. A self-consistent formulation is presented by generalizing the mass-flux formulation under the segmentally-constant approximation (SCA) to the grid–scale variabilities. The present formulation is expected to alleviate problems arising from increasing reso

APA, Harvard, Vancouver, ISO, and other styles

28

Frederiksen, Jorgen, and Terence O’Kane. "Entropy, Closures and Subgrid Modeling." Entropy 10, no. 4 (November 17, 2008): 635–83. http://dx.doi.org/10.3390/e10040635.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Frederiksen, Jorgen S., Terence J. O'Kane, and Meelis J. Zidikheri. "Subgrid modelling for geophysical flows." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1982 (January 13, 2013): 20120166. http://dx.doi.org/10.1098/rsta.2012.0166.

Full text

Abstract:

Recently developed closure-based and stochastic model approaches to subgrid-scale modelling of eddy interactions are reviewed. It is shown how statistical dynamical closure models can be used to self-consistently calculate the eddy damping and stochastic backscatter parameters, required in large eddy simulations (LESs), from higher resolution simulations. A closely related direct stochastic modelling scheme that is more generally applicable to complex models is then described and applied to LESs of quasi-geostrophic turbulence of the atmosphere and oceans. The fundamental differences between a

APA, Harvard, Vancouver, ISO, and other styles

30

Abbà, A., A. C. Cercignani, and L. Valdettaro. "Analysis of subgrid scale models." Computers & Mathematics with Applications 46, no. 4 (August 2003): 521–35. http://dx.doi.org/10.1016/s0898-1221(03)90014-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Sun, Mingyu. "Volume-tracking of subgrid particles." International Journal for Numerical Methods in Fluids 66, no. 12 (April 8, 2010): 1530–54. http://dx.doi.org/10.1002/fld.2331.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Casulli, Vincenzo. "Computational grid, subgrid, and pixels." International Journal for Numerical Methods in Fluids 90, no. 3 (January 27, 2019): 140–55. http://dx.doi.org/10.1002/fld.4715.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Wang, Liqiu. "Modelling of subgrid-scale fluxes." Chaos, Solitons & Fractals 34, no. 2 (October 2007): 368–75. http://dx.doi.org/10.1016/j.chaos.2006.03.049.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Abraham, G., H. Gerritsen, and G. J. H. Lindijer. "Subgrid tidally induced residual circulations." Continental Shelf Research 7, no. 3 (March 1987): 285–305. http://dx.doi.org/10.1016/0278-4343(87)90070-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Ke, Y., L. R. Leung, M. Huang, and H. Li. "Enhancing the representation of subgrid land surface characteristics in land surface models." Geoscientific Model Development Discussions 6, no. 1 (March 28, 2013): 2177–212. http://dx.doi.org/10.5194/gmdd-6-2177-2013.

Full text

Abstract:

Abstract. Land surface heterogeneity has long been recognized as important to represent in the land surface models. In most existing land surface models, the spatial variability of surface cover is represented as subgrid composition of multiple surface cover types. In this study, we developed a new subgrid classification method (SGC) that accounts for the topographic variability of the vegetation cover. Each model grid cell was represented with a number of elevation classes and each elevation class was further described by a number of vegetation types. The numbers of elevation classes and vege

APA, Harvard, Vancouver, ISO, and other styles

36

Zhang, Zhibo, Hua Song, Po-Lun Ma, Vincent E. Larson, Minghuai Wang, Xiquan Dong, and Jianwu Wang. "Subgrid variations of the cloud water and droplet number concentration over the tropical ocean: satellite observations and implications for warm rain simulations in climate models." Atmospheric Chemistry and Physics 19, no. 2 (January 28, 2019): 1077–96. http://dx.doi.org/10.5194/acp-19-1077-2019.

Full text

Abstract:

Abstract. One of the challenges in representing warm rain processes in global climate models (GCMs) is related to the representation of the subgrid variability of cloud properties, such as cloud water and cloud droplet number concentration (CDNC), and the effect thereof on individual precipitation processes such as autoconversion. This effect is conventionally treated by multiplying the resolved-scale warm rain process rates by an enhancement factor (Eq) which is derived from integrating over an assumed subgrid cloud water distribution. The assumed subgrid cloud distribution remains highly unc

APA, Harvard, Vancouver, ISO, and other styles

37

Zidikheri, Meelis J., and Jorgen S. Frederiksen. "Stochastic Subgrid Parameterizations for Simulations of Atmospheric Baroclinic Flows." Journal of the Atmospheric Sciences 66, no. 9 (September 1, 2009): 2844–58. http://dx.doi.org/10.1175/2009jas3036.1.

Full text

Abstract:

Abstract A stochastic subgrid modeling method is used to parameterize horizontal and vertical subgrid-scale transfers in large-eddy simulations (LESs) of baroclinic flows with large-scale jets and energy spectra typical of the atmosphere. The approach represents the subgrid-scale eddies for LES (at resolutions of T63 and T31) by a stochastic model that takes into account the memory effects of turbulent eddies. The statistics of the model are determined from a higher-resolution (T126) direct numerical simulation (DNS). The simulations use a quasigeostrophic two-level model and the subgrid terms

APA, Harvard, Vancouver, ISO, and other styles

38

Zhang, Yan, and Yinnian He. "A Subgrid Model for the Time-Dependent Navier-Stokes Equations." Advances in Numerical Analysis 2009 (September 6, 2009): 1–20. http://dx.doi.org/10.1155/2009/494829.

Full text

Abstract:

We propose a stabilized subgrid finite-element method for the two-dimensional (2D) nonstationary incompressible Naver-Stokes equation (NSE). This method yields a subgrid eddy viscosity which does not act on the large flow structures. The proposed eddy viscous term is constructed by a fluctuation operator based on an L2-projection. The fluctuation operator can be implemented by the L2-projection from high-order interpolation finite-element spaces to the low-order interpolation finite-element spaces. In this paper, P2/P1 mixed finite-element spaces are adopted to implement the calculation and th

APA, Harvard, Vancouver, ISO, and other styles

39

Yano, J. I. "Mass-flux subgrid-scale parameterization in analogy with multi-component flows: a formulation towards scale independence." Geoscientific Model Development Discussions 4, no. 4 (November 24, 2011): 3127–60. http://dx.doi.org/10.5194/gmdd-4-3127-2011.

Full text

Abstract:

Abstract. The mass-flux parameterization formulation is generalized by taking an analogy of the large-scale atmospheric flow with multi-component flows. This generalization permits to include any subgrid-scale variability into the mass-flux parameterization. Those include stratiform clouds as well as cold pools in the boundary layer. An important finding under the present formulation is that the subgrid-scale quantities are advected by the velocities characteristic of given subgrid-scale components (subcomponent flows), rather than by the large-scale flows as simply defined by grid-box average

APA, Harvard, Vancouver, ISO, and other styles

40

Tonttila, J., H. Järvinen, and P. Räisänen. "Explicit representation of subgrid variability in cloud microphysics yields weaker aerosol indirect effect in the ECHAM5-HAM2 climate model." Atmospheric Chemistry and Physics 15, no. 2 (January 19, 2015): 703–14. http://dx.doi.org/10.5194/acp-15-703-2015.

Full text

Abstract:

Abstract. The impacts of representing cloud microphysical processes in a stochastic subcolumn framework are investigated, with emphasis on estimating the aerosol indirect effect. It is shown that subgrid treatment of cloud activation and autoconversion of cloud water to rain reduce the impact of anthropogenic aerosols on cloud properties and thus reduce the global mean aerosol indirect effect by 19%, from −1.59 to −1.28 W m−2. This difference is partly related to differences in the model basic state; in particular, the liquid water path (LWP) is smaller and the shortwave cloud radiative forcin

APA, Harvard, Vancouver, ISO, and other styles

41

Hoffman, Johan. "Subgrid Modeling for Convection-Diffusion-Reaction in Two Space Dimensions Using a Haar Multiresolution Analysis." Mathematical Models and Methods in Applied Sciences 13, no. 10 (October 2003): 1515–36. http://dx.doi.org/10.1142/s021820250300301x.

Full text

Abstract:

In this paper we study a subgrid model based on extrapolation of a modeling residual, in the case of a linear convection-diffusion-reaction problem Lu=f in two dimensions. The solution u to the exact problem satisfies an equation Lhu=[f]h+Fh(u), where Lh is the operator used in the computation on the finest computational scale h, [f]h is the approximation of f on the scale h, and Fh(u) is a modeling residual, which needs to be modeled. The subgrid modeling problem is to compute approximations of Fh(u) without using finer scales than h. In this study we model Fh(u) by extrapolation from coarser

APA, Harvard, Vancouver, ISO, and other styles

42

Shaw, Tiffany A., and Theodore G. Shepherd. "A Theoretical Framework for Energy and Momentum Consistency in Subgrid-Scale Parameterization for Climate Models." Journal of the Atmospheric Sciences 66, no. 10 (October 1, 2009): 3095–114. http://dx.doi.org/10.1175/2009jas3051.1.

Full text

Abstract:

Abstract A theoretical framework for the joint conservation of energy and momentum in the parameterization of subgrid-scale processes in climate models is presented. The framework couples a hydrostatic resolved (planetary scale) flow to a nonhydrostatic subgrid-scale (mesoscale) flow. The temporal and horizontal spatial scale separation between the planetary scale and mesoscale is imposed using multiple-scale asymptotics. Energy and momentum are exchanged through subgrid-scale flux convergences of heat, pressure, and momentum. The generation and dissipation of subgrid-scale energy and momentum

APA, Harvard, Vancouver, ISO, and other styles

43

Park, Sungsu. "A Unified Convection Scheme (UNICON). Part I: Formulation." Journal of the Atmospheric Sciences 71, no. 11 (October 29, 2014): 3902–30. http://dx.doi.org/10.1175/jas-d-13-0233.1.

Full text

Abstract:

Abstract The author develops a unified convection scheme (UNICON) that parameterizes relative (i.e., with respect to the grid-mean vertical flow) subgrid vertical transport by nonlocal asymmetric turbulent eddies. UNICON is a process-based model of subgrid convective plumes and mesoscale organized flow without relying on any quasi-equilibrium assumptions such as convective available potential energy (CAPE) or convective inhibition (CIN) closures. In combination with a relative subgrid vertical transport scheme by local symmetric turbulent eddies and a grid-scale advection scheme, UNICON simula

APA, Harvard, Vancouver, ISO, and other styles

44

Tonttila, J., P. Räisänen, and H. Järvinen. "Monte Carlo-based subgrid parameterization of vertical velocity and stratiform cloud microphysics in ECHAM5.5-HAM2." Atmospheric Chemistry and Physics 13, no. 15 (August 6, 2013): 7551–65. http://dx.doi.org/10.5194/acp-13-7551-2013.

Full text

Abstract:

Abstract. A new method for parameterizing the subgrid variations of vertical velocity and cloud droplet number concentration (CDNC) is presented for general circulation models (GCMs). These parameterizations build on top of existing parameterizations that create stochastic subgrid cloud columns inside the GCM grid cells, which can be employed by the Monte Carlo independent column approximation approach for radiative transfer. The new model version adds a description for vertical velocity in individual subgrid columns, which can be used to compute cloud activation and the subgrid distribution o

APA, Harvard, Vancouver, ISO, and other styles

45

Malaspinas, Orestis, and Pierre Sagaut. "Consistent subgrid scale modelling for lattice Boltzmann methods." Journal of Fluid Mechanics 700 (April 30, 2012): 514–42. http://dx.doi.org/10.1017/jfm.2012.155.

Full text

Abstract:

AbstractThe lattice Boltzmann method has become a widely used tool for the numerical simulation of fluid flows and in particular of turbulent flows. In this frame the inclusion of subgrid scale closures is of crucial importance and is not completely understood from the theoretical point of view. Here, we propose a consistent way of introducing subgrid closures in the BGK Boltzmann equation for large eddy simulations of turbulent flows. Based on the Hermite expansion of the velocity distribution function, we construct a hierarchy of subgrid scale terms, which are similar to those obtained for t

APA, Harvard, Vancouver, ISO, and other styles

46

Dorrestijn, J., D. T. Crommelin, J. A. Biello, and S. J. Böing. "A data-driven multi-cloud model for stochastic parametrization of deep convection." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1991 (May 28, 2013): 20120374. http://dx.doi.org/10.1098/rsta.2012.0374.

Full text

Abstract:

Stochastic subgrid models have been proposed to capture the missing variability and correct systematic medium-term errors in general circulation models. In particular, the poor representation of subgrid-scale deep convection is a persistent problem that stochastic parametrizations are attempting to correct. In this paper, we construct such a subgrid model using data derived from large-eddy simulations (LESs) of deep convection. We use a data-driven stochastic parametrization methodology to construct a stochastic model describing a finite number of cloud states. Our model emulates, in a computa

APA, Harvard, Vancouver, ISO, and other styles

47

Zhou, Ye, and George Vahala. "Aspects of subgrid modelling and large-eddy simulation of magnetohydrodynamic turbulence." Journal of Plasma Physics 45, no. 2 (April 1991): 239–49. http://dx.doi.org/10.1017/s0022377800015671.

Full text

Abstract:

Subgrid-scale closures for magnetohydodynamic (MHD) turbulence are examined using the filtering technique. From the similarities between incompressible MHD turbulence and its hydrodynamic counterpart, as well as ideas from dynamo theory, a subgrid model is constructed from the large-eddy simulation (LES) of MHD turbulence. This model should find applicability in treating LES of the reversed-field pinch.

APA, Harvard, Vancouver, ISO, and other styles

48

Isakov, Vlad, John S. Irwin, and Jason Ching. "Using CMAQ for Exposure Modeling and Characterizing the Subgrid Variability for Exposure Estimates." Journal of Applied Meteorology and Climatology 46, no. 9 (September 1, 2007): 1354–71. http://dx.doi.org/10.1175/jam2538.1.

Full text

Abstract:

Abstract Atmospheric processes and the associated transport and dispersion of atmospheric pollutants are known to be highly variable in time and space. Current air-quality models that characterize atmospheric chemistry effects, for example, the Community Multiscale Air Quality model (CMAQ), provide volume-averaged concentration values for each grid cell in the modeling domain given the stated conditions. Given the assumptions made and the limited set of processes included in any model’s implementation, there are many sources of “unresolved” subgrid variability. This raises the question of the

APA, Harvard, Vancouver, ISO, and other styles

49

Bengtsson, Lisa, Heiner Körnich, Erland Källén, and Gunilla Svensson. "Large-Scale Dynamical Response to Subgrid-Scale Organization Provided by Cellular Automata." Journal of the Atmospheric Sciences 68, no. 12 (December 1, 2011): 3132–44. http://dx.doi.org/10.1175/jas-d-10-05028.1.

Full text

Abstract:

Abstract Because of the limited resolution of numerical weather prediction (NWP) models, subgrid-scale physical processes are parameterized and represented by gridbox means. However, some physical processes are better represented by a mean and its variance; a typical example is deep convection, with scales varying from individual updrafts to organized mesoscale systems. This study investigates, in an idealized setting, whether a cellular automaton (CA) can be used to enhance subgrid-scale organization by forming clusters representative of the convective scales and thus yield a stochastic repre

APA, Harvard, Vancouver, ISO, and other styles

50

Hirt, Mirjam, Stephan Rasp, Ulrich Blahak, and George C. Craig. "Stochastic Parameterization of Processes Leading to Convective Initiation in Kilometer-Scale Models." Monthly Weather Review 147, no. 11 (October 11, 2019): 3917–34. http://dx.doi.org/10.1175/mwr-d-19-0060.1.

Full text

Abstract:

Abstract Kilometer-scale models allow for an explicit simulation of deep convective overturning but many subgrid processes that are crucial for convective initiation are still poorly represented. This leads to biases such as insufficient convection triggering and late peak of summertime convection. A physically based stochastic perturbation scheme (PSP) for subgrid processes has been proposed (Kober and Craig) that targets the coupling between subgrid turbulence and resolved convection. The first part of this study presents four modifications to this PSP scheme for subgrid turbulence: an autor

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!