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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.

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Sub groups
D-Flow Flexible Mesh
DELWAQ

Cohesive sediments & muddy systems

 


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Why does coupling ignore sediment files to couple?

GS
Gholamreza Shiravani, modified 7 Months ago.

Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

Hi D3D community,

After coupling using ddcouple for D-FLOW in cluster, I recieve a single file for all Parameters (.sal, .tau, ...) except of Sediment fractions! However, like all other Parameters (e.g. Salinity (.sal)) I have for each Sediment fraction, ist corresponding file for each node (.sed01,.sed02,.0sed3). Could anyone tell me how can I generate after coupling a singl file for each Sediment fraction ? and when I give These single files for each Sediment fraction, how and where they willbe used in WAQ?

AM
Arjen Markus, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

The answer to that one is simple: we never had a request for that.

I am not sure how much work it would be to incorporate a new parameter in the coupling step.

GS
Gholamreza Shiravani, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

Thanks Arjen for your answer. I have a successfull 3D-Modell from D-FLOW, and a good Modell using Delwaq for IMs using coupling and running with Delwaq. Now the main purpose is to have in Delwaq for whole domain the corresponding water column sediment concentration from D-FLOW to relate the Delwaq-substances  (like IM1,IM2 and IM3) to the sediment fractional concentrations (which come from D-FLOW). Could you tell me how can I modify the coupling file to do it? It is the main part of my Research :).

AM
Arjen Markus, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

There appears to be a workaround: temporarily rename the files *.sed01 to *.sal (in every domain directory) and rerun the ddcouple program. That gives you a file that contains the first sediment fraction for all domains taken together. The same of *.sed02 and *.sed03, etc. A bit cumbersome perhaps but at least it will give you what you need rightaway. We are discussing the necessary changes to the program - it is odd that ddcouple does not do this already, but then a program is only as smart as you make it ;).

GS
Gholamreza Shiravani, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

Hi Arjen, I run my D-FLOW Modell with four sediment fractions by online-coupling, and realized that three groups of files are generated extra than the time, when I run D-FLOW without sediment : .resflx, .sed and .sedflx (please see them in resflx.png). Now the questions are:

1-what type of data are in these three file-formats?

2-which of them is sediment concentration, which could be used in Delwaq processes?

In Manuals (D-FLOW, Delwaq as wll as Sediment Water Interaction), I did not find description about them. Then I searched sedflx in internet and I found it in Doxygen file of waq_processes sedflx as a variable in the src (please see it in sedflx.png). Now, I asked myself this question, when sediment files are not coupled using ddcouple, why are they already included in Delwaq subroutines :)? If .sedflx is the targeted file for sediment concentration in Delwaq (I do not know :), whether it is, please correct me!)

3-How can I include sedflx for four fractions? Should I define variables like sedflx01, sedflx02, ..., sedflx04 in source code and then define the sedflx=sum(sedflx01, sedflx02, ..., sedflx04)?

JP
Jill Padilla, modified 1 Month ago.

RE: Why does coupling ignore sediment files to couple?

Youngling Posts: 1 Join Date: 10/11/19 Recent Posts
Arjen Markus:

There appears to be a workaround: temporarily rename the files *.sed01 to *.sal (in every domain directory) and rerun the ddcouple program. That gives you a file that contains the first sediment fraction for all domains taken together. The same of *.sed02 and *.sed03, short life online etc. A bit cumbersome perhaps but at least it will give you what you need rightaway. We are discussing the necessary changes to the program - it is odd that ddcouple does not do this already, but then a program is only as smart as you make it ;).
Thank you for the advice, that sounds reasonable!
AM
Arjen Markus, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

I checke dthe source code for these files - they represent the  cumulative sedimentation and resuspension flux. They have the very same structure as all the other files, so in principle you could combine them into a single domain in the same way as the .sed00 etc files. However, I have no idea how they would be used in the processes. Fluxes simply do not fit into the characteristics of the process parameters that Delft3D-WAQ can use (a constant, a time series, a constant varying over the segments - parameter in Delft3D-WAQ parliance - or a segment function).

Hm, if I stretch my imagination a bit, then such fluxes might be used as zeroth-order terms - the process for atmospheric deposition might be used as a "proxy". The problem is, however, that the documentation says the "cumulative" flux, but for this to work properly, you need the instantaneous flux, otherwise you get a "double" integration.

For the record: I have never seen these files before myself.

GS
Gholamreza Shiravani, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

I would like to use the sediment concentration results in each cell from D-FLOW as a conditional Statement in Delwaq-src  for IM. To talk more clear, I would say to delwaq that in any computational cell of delwaq if the corresponding Sediment concentration in D-FLOW is greather than a critical value, then the settling velocity of IM should be overwritten by sediment settling velocity. Do you know a simpler way than coupling the Sediment concentration from D-FLOW with Delwaq and then calling them in Delwaq-src (sedim.f)?

AM
Arjen Markus, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

I am not sure what you want to do that for, but the technique would be:

- Modifiy the process definition, so that you have an extra input parameter - the sediment concentration from D-FLOW

- Add the necessary code to the sedimentation routine

You can then use the input facilities from D-Water Quality to import the D-FLOW sediment files as a segment function.

That does require a few technical steps and that is not for the faint of heart ;), but then again, it is not really difficult.

GS
Gholamreza Shiravani, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

Thanks Arjen for your answer. I followed your instructions. I generated a file using coupling for Sediment fractions by renaming all .tem to another format like .tim :) and renaming the Sediment fraction to .tem. Then, coupling was successful and I got a single file with .tem-format for fractional sediment concentration. After that, as you told, I tried to define a new Input in sedim.f-file and now I do not know which IP-number (IP1 or IP2 or ...) in PMSA is responsible to read generated .tem-file? (please have a look at attached screenshot)

GS
Gholamreza Shiravani, modified 6 Months ago.

RE: Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

Hi Arjen, I followed your instructions as you can see in attached photos, and then changed the code of sedimentation (please see the attached photos) and compiled it again, the compilation is successful, but after using the new compiled version, there is no difference between the results with before compiling! Could you tell me how can I fix this Problem?

Many thanks.

GS
Gholamreza Shiravani, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Padawan Posts: 60 Join Date: 6/25/16 Recent Posts

You mean all of These 12 files have the same values! The .sed04, which is the Sediment concentration of fraction 4 is exactly .sed03! Are you sure
? then how can I access to the fractional concentrations from D-FLOW after online coupling?

AM
Arjen Markus, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

No, I mean that the STRUCTURE is the same, not the contents. You can treat them in the same way as all the others.

AM
Arjen Markus, modified 7 Months ago.

RE: Why does coupling ignore sediment files to couple?

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

I have talked to my colleague - we conclude that these files are most probably written as part of  an experimental feature. It is probably best to ignore them - see my previous message about how they would have to be used.