Migration status

  • Home Page: Activity map.

intro story DELWAQ

DELWAQ

DELWAQ is the engine of the D-Water Quality and D-Ecology programmes of the Delft3D suite. It is based on a rich library from which relevant substances and processes can be selected to quickly put water and sediment quality models together.

The processes library covers many aspects of water quality and ecology, from basic tracers, dissolved oxygen, nutrients, organic matter, inorganic suspended matter, heavy metals, bacteria and organic micro-pollutants, to complex algae and macrophyte dynamics. High performance solvers enable the simulation of long periods, often required to capture the full cycles of the processes being modelled.

The finite volume approach underlying DELWAQ allows it to be coupled to both the structured grid hydrodynamics of the current Delft3D-FLOW engine and the upcoming D-Flow Flexible Mesh engine (1D-2D-3D) of the Delft3D Flexible Mesh Suite (or even other models such as TELEMAC).

'DELWAQ in open source' is our invitation to all leading experts to collaborate in further development and research in the field of water quality, ecology and morphology using Delft3D. Feel free to post your DELWAQ related questions or comments in this dedicated forum space. If you are new to DELWAQ, the tutorial (in the user manual) is a good place to start. A list of DELWAQ related publications is available here.

** PLEASE TAG YOUR POST! **

 

 

Sub groups
D-Flow Flexible Mesh
DELWAQ

Cohesive sediments & muddy systems

 


Message Boards

suspended sediment and salinity from FLOW to WAQ?

ZW
Zhanxian Wang, modified 1 Year ago.

suspended sediment and salinity from FLOW to WAQ?

Padawan Posts: 35 Join Date: 4/11/12 Recent Posts
Hi, all,

I am a beginner on DELWAQ. I want to know that when doing the coupling between FLOW and WAQ, can the suspended sediment (cohesive) and salinity be imported directly from FLOW results to WAQ? From the user manual and some discussions here, it looks like temperature can be imported directly. Has anyone tried salinity and/or suspended sediments?

Thanks,
Jonathan
Ben Williams, modified 1 Year ago.

RE: suspended sediment and salinity from FLOW to WAQ?

Jedi Knight Posts: 114 Join Date: 3/23/11 Recent Posts
Hi Johnathon (or Zhanxian?),

I'm pretty certain WAQ imports salinity and temperature from FLOW, perhaps just as density field, as ambient water density is needed in order to simulate outfalls in WAQ. However I am not aware of any capability to import sediment quantities from MOR (via FLOW) to WAQ.

WAQ does have a sediment transport module, albeit much simpler than MOR in terms of physics and numbers of sediment fractions considered.

Are you interested in using suspended sediment concentration to estimate light extinction?

Best regards,

Ben
AM
Arjen Markus, modified 1 Year ago.

RE: suspended sediment and salinity from FLOW to WAQ? (Answer)

Jedi Knight Posts: 222 Join Date: 1/26/11 Recent Posts
Ben is quite right, although there is no particular reason why the sediment results should not be transported to WAQ. It has simply never been considered, although that is for good reasons emoticon. The point is that MOR is about morphological changes and WAQ considers sediment as a vehicle for the transport of pollutants and as one of the compoments that determine the light climate (via extinction). That is, WAQ mostly considers the fine fraction - anything smaller than "sand".
As for salinity: if the hydrodynamic calculation includes salinity, then this will be exported by the builtin coupling (or by the external coupling program) as a file with the extension ".sal". Likewise: the temperature is in a file with extension ".tem", the vertical diffusion coefficient in ".vdf" and the shear stress in a file ".tau". These quantities can be imported as so-called segment functions. (It would be possible to do this for the sediment concentrations as well, but as I stated above, the need has never arisen.)
ZW
Zhanxian Wang, modified 1 Year ago.

RE: suspended sediment and salinity from FLOW to WAQ?

Padawan Posts: 35 Join Date: 4/11/12 Recent Posts
Hi, Ben and Arjen:

Thanks for the quick response. The study I have includes cohesive sediment related channel morphological change and cohesive sediment related water quality. I definitely will run FLOW model with salinity and cohesive sediment; however, for the water quality model, I want to avoid to calculate cohesive sediment again if I can transfer it from the FLOW model. Will I get the same cohesive sediment concentration in the water column from DELWAQ as the FLOW model if I use the same model grid and sediment characteristics?

From the coupling WAQ output from FLOW model, there are several files that look like related to sediment as shown in the attached figure: *.sed01, *.resflx01, *.sedflx01. What are these files? If they are related to sediment, can they be used directly in DELWAQ as inputs similar to salinity and temperature?

Thanks,
Jonathan
GS
Gholamreza Shiravani, modified 4 Months ago.

RE: suspended sediment and salinity from FLOW to WAQ?

Padawan Posts: 53 Join Date: 6/25/16 Recent Posts

Hi Wang,

did you find finally the solution to Import Sediment concentration from D-FLOW to WAQ? After coupling I have the corresponding file for all Parameters except of Sediment? How did you couple the Sediment files to use in WAQ? I will be appreciate if you answer my question.

GS
Gholamreza Shiravani, modified 3 Months ago.

RE: suspended sediment and salinity from FLOW to WAQ?

Padawan Posts: 53 Join Date: 6/25/16 Recent Posts

Hi Markus, could you tell me then how will Delwaq realize a segment, which is already filled with sediment in Morph, should excluded from computations in Delwaq? I mean, Delwaq without Morph and sediment modules from FLOW can not practically  provide right results!

AM
Arjen Markus, modified 3 Months ago.

RE: suspended sediment and salinity from FLOW to WAQ?

Jedi Knight Posts: 222 Join Date: 1/26/11 Recent Posts

I think you misunderstand something here: MOR is about the transport of sand (and other non-cohesive sediment), whereas DELWAQ is about cohesive sediment, so silt, mud, clay particles, also fine particulate organic material. The transport phenomena involved are quite different.