srdg april2011

Stromness, 27th February 2011

Dr. Susana Baston MeiraICIT- International Centre for Island Technology

Heriot-Watt University, Orkney Campus

Stromness, 27th February 2011

Research Team

Dr Susana Baston Meira, ICIT H-W

Dr Rob Harris, ICIT H-W

Prof Jon Side, ICIT H-W

Dr Karl Stephen, IPE H-W

Prof Margot Gerritsen, Stanford University

Stromness, 27th February 2011

Contents

Introduction to Numerical Flow Modelling

SUNTANS Model description

Implementation at PF & OW

Focus of Present Research

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Introduction to Numerical Flow Models

Description of water column structure

Estimation of energy resource

Evaluation of scales of resolution

Physical environment changes

Shoreline morphodynamic alteration

Larvae and pollutants transport

Of Interest, 2D & 3D models

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Introduction to Numerical Flow Models

Information in z-coordinate3-D Hydrodynamic Models

ADCIRCA (parallel) ADvanced CIRCulation model for Oceanic, Coastal and

Estuarine watershttp://www.unc.edu/ims/adcirc/

COHERENSCOupled Hydrodinamic Ecological model for REgioNal Shelf Seas

http://www.mumm.ac.be/EN/Models/Coherens/index.php

FVCOMFinite Volume Comunnity Ocean Model

http://fvcom.smast.umassd.edu/FVCOM/index.html

MIKE-3Dhttp://mikebydhi.com/Products/CoastAndSea/MIKE3.aspx

POMPrinceton Ocean Model

http://www.aos.princeton.edu/WWWPUBLIC/htdocs.pom/

ROMSRegional Ocean Model System

http://www.myroms.org/

SUNTANSStanford Unstructured Non-hydrostatic Terrain following Adaptive

Navier-Stokes Simulatorhttp://suntans.stanford.edu/

TELEMAC-3Dhttp://www.telemacsystem.com/

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SUNTANS Model: Definition

SUNTANSSUNTANS is a numerical model designed for the

simulation of complex, non-hydrostatic, coastal,

river and estuarine flows, with high resolution on

unstructured grids using parallel computers.

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SUNTANS Model: Primary Publications O. B. Fringer, M. Gerritsen, and R. L. Street, 2006. "An unstructured-grid, finite-volume, nonhydrostatic, parallel coastal-ocean simulator", Ocean Modelling, 14 (3-4), 139-278.

O. B. Fringer, 2009, "High-resolution 3D hydrodynamics and sediment transport modeling of San Francisco Bay“

O. B. Fringer, 2009, "Towards nonhydrostatic ocean modeling with large-eddy simulation“

B. Wang, O. B. Fringer, and E. S. Gross, 2010, "Understanding turbulent mixing in a partially stratified estuary using SUNTANS"

D. Kang and O. B. Fringer, 2010, "On the calculation of available potential energy in internal wave fields", J. Phys. Oceanogr., 40 (11), 2539-2545.

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SUNTANS Model: Why? Open source: Accessible to a wide research community

Three-dimensional approach: Resolves vertical flow characteristics

Unstructured grid: Provides exceptional resolution around fine-scale features

Parallel Implementation: Facilitates high resolution, efficient computational use

Active, developing, research community: H-W links with Stanford University

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SUNTANS Model: Open SourceWhy not Mike-3D?Commercial software

Why not Telemac?Only 2D open source

Why not FVCOM?Non-hydrostatic versionyet to be tested

UnstructuredUnstructured

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SUNTANS Model: UnstructuredUnstructured grid, Terrain-following adaptive

Structured grid Unstructured grid

z-coordinate isopycnalcoordinate

σ-coordinate

Vertical discretisation:

a) z-coordinate models

b) isopycnal models

c) σ-coordinate models

SUNTANS employs a z-level grid

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Fringer, O., McWilliams, J. & Street, R., 2006. A New Hybrid Model for Coastal Simulations. Oceanography, 19(1), 65-77.

SUNTANS Model: Nonhydrostatic

It is ideally suited to modelling regions of high turbulence including density gradients

SUNTANS is Non-hydrostatic

Solves vertical acceleration and friction

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Implementation: PF & OWComputational requirementsModel is installed on the IPE cluster in Edinburgh. It has 10-node of 8 processors. Operating system: Linux

Initial conditions:-- Quiescent free surface and velocity field-- No stratification

Boundary conditions:

They are given by the first eight tidal constituents computed by OTIS

38,342 cells, 20 levels, Δt=2s, Run Time 14 hours, Simulation 3 days, 6 processors

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Implementation: PF & OW

25708 cells, 20 z-levels,

Δt=2s, Run Time 12 hours, Simulation 3 days,

4 processors

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Implementation: PF & OW

38342 cells, 10 levels, Δt=5s, Run Time 1 day, Simulation 10 days, 2 processors

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Implementation: PF & OWPoint 1

Comparison SUNTANS-OTIS

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Implementation: PF & OW

The UKHO provided Gardline with three target locations for the deployments as follows:

SITE LATITUDE LONGITUDE DEPTH TIME DEPLOYED

1 58° 43’ 34”N

003° 14’ 11”W

82 m 12:30 14/09/01

2 58° 43’ 01”N

003° 05’ 09”W

80 m 12:01 14/09/01

3 58° 40’ 13”N

002° 58’ 35”W

71 m 11:35 14/09/01

Data: One month of velocity averagedevery 10 minutes

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Implementation: PF & OW

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Focus of Present Research Development of model, spatial and temporal resolution

Validation against field data / other theoretical models Improved bathymetry Seabed friction coefficient

Identification and Characterisation of PF waters Turbulence, identification of eddies Mixing process, density stratification

Evaluation of energy resource Velocity profile characteristics Energy extraction, available resource, farm size / layout

Environmental impacts Site characteristics, scale, layout, near / far field effects

Email: s.baston@hw.ac.uk

Web: http://www.icit.hw.ac.uk/

Thanks for your attention!

Stromness, 27th February 2011