dsd-nl 2014 - nghs flexible mesh - tetratech pilot oil spill modeling, freek scheel, deltares
Post on 26-Jan-2015
198 Views
Preview:
DESCRIPTION
TRANSCRIPT
www.tetratech.com
Baía de Guanabara
RJ – BRASIL
Delft3D FM
TETRA TECH Team:
Maria Fernanda Fiedler
Eduardo Yassuda
DELTARES:
Freek Scheel
Deltares Software Center
Baía de Guanabara (Guanabara Bay)
Guanabara Bay is located in the Southeastern Coast of Brazil, in the state of Rio de Janeiro
Rio de
Janeiro
Niterói
30 km
Baía de Guanabara (Guanabara Bay)
• Besides touristic relevance also economic activity: harbors, docks, shipyards, naval base and oil platform maintenance facilities availability of operational forecasts essential
Study background
• Set-up of an operational system for the Brazilian Navy to forecast wave propagation and 3D hydrodynamics in the Guanabara Bay.
Tetra Tech: Delft3D-FLOW and Delft-WAVE models
Deltares: FEWS operational system.
Brazilian Navy: field data and model boundary conditions from a regional model.
Complex area (coastline, narrow channel, island) makes it suitable for a Delft3D Flexible Mesh application
Objective DFM pilot case
• Set-up and compare the results of a D-Flow FM model with the conventional Delft3D model
Original Delft3D FLOW
Delft3D FM (a)
• Keeping the same grid and forcing
• Delft3D FM (b)
• New grid, same forcing
Delft3D-FLOW/Delft3D-FM (a) GRID
~200km
Delft3D-FLOW/Delft3D-FM (a) GRID
Hydrodynamic Model
Delft3D-FLOW/Delft3D-FM (a) • 3D model – 5 sigma layers (20% each layer)
Forcing
• Water Level 16 water level (time-series) boundaries based on HYCOM water level hourly
results (from Brazilian Navy Model)
• Wind and Pressure Wind (u and v comp.) and Pressure – spatial varying
• Discharge Boundaries 9 discharge (time-series) boundaries based on mean discharge values
• Thin dams / Dry points
• Observation Points
Hydrodynamic Model
Delft3D-FM (b) • 3D model – 5 sigma layers (20% each layer)
Forcing
• Water Level 23 water level (time-series) boundaries based on HYCOM water level hourly
results (from Brazilian Navy Model)
• Wind and Pressure Wind (u and v comp.) and Pressure – spatial varying
• Discharge Boundaries 9 discharge (time-series) boundaries based on mean discharge values
• Thin dams / Dry points
• Observation Points
Guanabara Bay - Delft3D-FLOW/Delft3D-FM (a) grid FM Delta Shell Interface
Delft3D-FLOW/Delft3D-FM (b) GRID
FM Delta Shell Interface
High resolution – bay entrance/ navigation channels
Low resolution – adjacent coastal
zone
RESULTS
TIME SERIES
• Water Level Measurements were compared with all the scenarios (FLOW, FM (a) and FM (b)).
• Water level results from FLOW x FM (a) were compared, for the same station.
• Surface and bottom velocity results from FLOW x FM (a) were also compared, for the same station.
MAP RESULTS
• Delft3D-FLOW x Delft3D-FM (a)/ surface velocity
• Delft3D-FLOW x Delft3D-FM (b)/ surface velocity
Comparisons with Water Level
Measurements
Delft3D-FLOW
Delft3D-FM (a)
Delft3D-FM (b)
Delft3D FLOW x Delft3D-FM (a)
Water Level
Velocity (surface)
Delft3D FLOW x Delft3D-FM (a)
Velocity (bottom)
Delft3D FLOW x Delft3D-FM (a)
Delft3D FLOW x Delft3D-FM (a)
Map Results
• The main
differences are
observed close
to irregular
coastal areas,
narrows and
islands.
Map results
Vectors are very
similiar
(magnitude and
direction)
Differences in eddy formation
Delft3D FLOW x Delft3D-FM (b)
FLOW
FM (b)
• Stronger velocities nearby the bay entrance;
• Differences on eddy formation;
Dry Points
defined on
Delft3D-FLOW
Dry Points
NOT defined
on Delft3D-FM
WITHOUT dry points/ thim dams/ “.pli” files
WITH dry points/ thim dams/ “.pli” files
Conclusions
• The tests in Guanabara Bay showed a good agreement between Delft3D-FM results and measurements and also with Delft3D-FLOW results;
• Delft3D-FM grid represent a great option to solve the Guanabara Bay complex coastline with a high resolution, without a large number of cells outside the bay. However, the grid needs be further improved in some regions;
Conclusions
• During the pilot case some difficulty was found and some functionalities that did not work. Tetra Tech team used more the old interface than the Delta Shell FM because some functions did not work in the new one. All of the steps that Tetra Tech team could not solve were resolved by the ambassadors;
• Tetra Tech users felt that Delft3D-FM interface still have to be adjusted (more automated functions / less manual), mainly in the part of grid generation, to reduce the time of grid construction;
Conclusions
• It is Tetra Tech conclusion that Delft3D-FM is a great improvement for Delft3D, and we are very interested in continue the partnership with Deltares in the final development of the system;
• Congratulation to all Deltares development team!!!
Thank you
Fernanda.Fiedler@tetratech.com
Eduardo.Yassuda@tetratech.com
Freek.Scheel@deltares.nl
top related