Research output: Scientific - peer-review › Article

**An axisymmetric non-hydrostatic model for double-diffusive water systems.** / Hilgersom, Koen; Zijlema, Marcel; van de Giesen, Nick.

Research output: Scientific - peer-review › Article

Hilgersom, K, Zijlema, M & van de Giesen, N 2018, 'An axisymmetric non-hydrostatic model for double-diffusive water systems' *Geoscientific Model Development*, vol 11, pp. 521-540. DOI: 10.5194/gmd-11-521-2018

Hilgersom, K., Zijlema, M., & van de Giesen, N. (2018). An axisymmetric non-hydrostatic model for double-diffusive water systems. *Geoscientific Model Development*, *11*, 521-540. DOI: 10.5194/gmd-11-521-2018

Hilgersom K, Zijlema M, van de Giesen N. An axisymmetric non-hydrostatic model for double-diffusive water systems. Geoscientific Model Development. 2018 Feb 6;11:521-540. Available from, DOI: 10.5194/gmd-11-521-2018

@article{a92701716bc340e88a2780092380da9f,

title = "An axisymmetric non-hydrostatic model for double-diffusive water systems",

abstract = "The three-dimensional (3-D) modelling of water systems involving double-diffusive processes is challenging due to the large computation times required to solve the flow and transport of constituents. In 3-D systems that approach axisymmetry around a central location, computation times can be reduced by applying a 2-D axisymmetric model set-up. This article applies the Reynolds-averaged Navier–Stokes equations described in cylindrical coordinates and integrates them to guarantee mass and momentum conservation. The discretized equations are presented in a way that a Cartesian finite-volume model can be easily extended to the developed framework, which is demonstrated by the implementation into a non-hydrostatic free-surface flow model. This model employs temperature- and salinity-dependent densities, molecular diffusivities, and kinematic viscosity. One quantitative case study, based on an analytical solution derived for the radial expansion of a dense water layer, and two qualitative case studies demonstrate a good behaviour of the model for seepage inflows with contrasting salinities and temperatures. Four case studies with respect to double-diffusive processes in a stratified water body demonstrate that turbulent flows are not yet correctly modelled near the interfaces and that an advanced turbulence model is required.",

keywords = "axisymmetric model, CFD modelling, density-driven flow, double diffusion, double-diffusive convection, heat transport, non-hydrostatic model, numerical modelling, salt transport, salt-fingers, SWASH (Simulating WAves till SHore)",

author = "Koen Hilgersom and Marcel Zijlema and {van de Giesen}, Nick",

year = "2018",

month = "2",

doi = "10.5194/gmd-11-521-2018",

volume = "11",

pages = "521--540",

journal = "Geoscientific Model Development",

issn = "1991-959X",

publisher = "Copernicus",

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AU - Hilgersom,Koen

AU - Zijlema,Marcel

AU - van de Giesen,Nick

PY - 2018/2/6

Y1 - 2018/2/6

N2 - The three-dimensional (3-D) modelling of water systems involving double-diffusive processes is challenging due to the large computation times required to solve the flow and transport of constituents. In 3-D systems that approach axisymmetry around a central location, computation times can be reduced by applying a 2-D axisymmetric model set-up. This article applies the Reynolds-averaged Navier–Stokes equations described in cylindrical coordinates and integrates them to guarantee mass and momentum conservation. The discretized equations are presented in a way that a Cartesian finite-volume model can be easily extended to the developed framework, which is demonstrated by the implementation into a non-hydrostatic free-surface flow model. This model employs temperature- and salinity-dependent densities, molecular diffusivities, and kinematic viscosity. One quantitative case study, based on an analytical solution derived for the radial expansion of a dense water layer, and two qualitative case studies demonstrate a good behaviour of the model for seepage inflows with contrasting salinities and temperatures. Four case studies with respect to double-diffusive processes in a stratified water body demonstrate that turbulent flows are not yet correctly modelled near the interfaces and that an advanced turbulence model is required.

AB - The three-dimensional (3-D) modelling of water systems involving double-diffusive processes is challenging due to the large computation times required to solve the flow and transport of constituents. In 3-D systems that approach axisymmetry around a central location, computation times can be reduced by applying a 2-D axisymmetric model set-up. This article applies the Reynolds-averaged Navier–Stokes equations described in cylindrical coordinates and integrates them to guarantee mass and momentum conservation. The discretized equations are presented in a way that a Cartesian finite-volume model can be easily extended to the developed framework, which is demonstrated by the implementation into a non-hydrostatic free-surface flow model. This model employs temperature- and salinity-dependent densities, molecular diffusivities, and kinematic viscosity. One quantitative case study, based on an analytical solution derived for the radial expansion of a dense water layer, and two qualitative case studies demonstrate a good behaviour of the model for seepage inflows with contrasting salinities and temperatures. Four case studies with respect to double-diffusive processes in a stratified water body demonstrate that turbulent flows are not yet correctly modelled near the interfaces and that an advanced turbulence model is required.

KW - axisymmetric model

KW - CFD modelling

KW - density-driven flow

KW - double diffusion

KW - double-diffusive convection

KW - heat transport

KW - non-hydrostatic model

KW - numerical modelling

KW - salt transport

KW - salt-fingers

KW - SWASH (Simulating WAves till SHore)

UR - http://resolver.tudelft.nl/uuid:a9270171-6bc3-40e8-8a27-80092380da9f

U2 - 10.5194/gmd-11-521-2018

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M3 - Article

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EP - 540

JO - Geoscientific Model Development

T2 - Geoscientific Model Development

JF - Geoscientific Model Development

SN - 1991-959X

ER -

ID: 38396183