I have a problem with temperature modeling in a pond - Delwaq - Delft3D
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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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I have a problem with temperature modeling in a pond
Fatemeh GholamiMahyari, modified 3 Years ago.Youngling Posts: 23 Join Date: 4/8/16 Recent Posts
I want to model a wastewater pond in Delft waq my main focus is in algae. I have a problem with the temperature modelling in my pond. in the model pond is still cold even in the warm season. I checked everything radiation, ambient temp seems ok. However in the flow temp seems correctly simulated. I also edit my inp file in order to use temp result from delft flow but nothing changed. I attached ,y inp file. so maybe somebody can help me. I should add I model just temp in my model it is ok and my pond get warm in th summer. but with my combination substances and even algae substances in the forum it does not work. Please help me I am so confused.
Thanks for helping me .
I finally could made WAQ to read temp from Flow. But I am so confused why I active the water temp and heat exchange process water temp modeled is shockingly low at summer (Attached pic). But when I did not chose temp and heat exchange process it worked normally. By the way I have the same problem with my Algae modeling the result did not seem OK. maybe the process did not work correctly. I attached inp and lsp file that belongs to the picture.
I would appreciate your help. I am so confused these days with my model.
Thanks a lot for everything
- The TEMPERATUR process in DELWAQ is configured to produce the surplus temperature (in the WQ parameter ModTemp). The result is shown in the first picture
- You also use the result of the hydrodynamic model and store this in the process parameter Temp. The consequence is that the output "Temp" from the TEMPERATUR process is lost
The second picture shows an ambient temperature (directly from the hydrodynamics) that is very close to 20 degrees. Apparently this is the result from the way the hydrodynamic model has been set up.
However, the TEMPERATUR process uses the process parameter NatTemp, which is set to a constant 15 degrees. That parameter presents the equilibrium temperature. What you probably want is to use the hydrodynamic output as the value for NatTemp. Change the input such that NatTemp is read from the file com-G7_DD_run2.tem instead of Temp and define Temp as an output parameter.
Now I know what is going on.I thought that water temperature (upper picture in my last post) is what WAQ uses in their calculation to simulate Algae and other nutrient. So I thought that is the reason why there is no algae even in the summer in my pond.
IS Nat temp what WAQ use for simulating algae?
I attached my result below. Despite of high nutrient, temp and irradiation even in July there is no alga in my pond. that is a big surprise. Algae and vegetation decrease from first of April to zero at the first of May which is wrong. I do not know where is the problem.
Thanks again for helping me. I really appreciate your support.
Input for [BLOOM ] BLOOM II algae module
WARNING : activated process can NOT be switched on
Not found:[ExtVlPhyt ] VL extinction by phytoplankton
Not found:[Si ] dissolved Silica (Si)
So there are two things missing which prevent the BLOOM process from being activated (and since this process calculates how much microalgae will grow, the green algae simply slowly disappear):
- You do not have dissolved silica (Si) as a substance. Even though you have no diatoms included, BLOOM expects to be able to determine how Si can be taken up.
- The process parameter ExtVlPhyt is missing - it should be the output of an additional process
To solve the first problem: add Si as a substance to the substances file.
To solve the second problem, you need to add the process EXTINABVLP - this calculates the total extinction ExtVlPhyt as algae experience it.
Now, there is also a problem with the macrophytes - if you look in the .lsp file you will notice that the proces MacroPhyt1 is not activated, because MnTempSM01 is missing. This can be solved by adding the process MACNUTSM01 to the list (you have the corresponding process for the second macrophyte type already). I am not sure that with the addition of that process the macrophytes will grow as expected. But let's first make these changes.
Since I tried to do all you said and re run my model with new changes. it seems OK without any warning or error in WAQ1.
But when it comes to simulation it does not work the error is as below:
INTEGRATION ROUTINE = 15
Problem in RADMAC
It seems my new process should be OK. But I do not know what should I do with this errro. Could you help me. I attached lsp and inp file
You need to add the following processes:
Coverage (calculates what fraction ofthe surface is occupied by emerging macrophytes)
ExtMacroVl (light extinction i.r.t. macrophytes)
MaxMacro (maximum biomass for the macrophytes)
Rad_SM02 (that is missing, it calculates how much light is available for the macrophyte)
What is, by the way, the reason to specify the bottom segment number, IBotSeg? It is calculated from the geometry normally.
I tried to do what you said and add the process. I have a problem with MaxMacro (maximum biomass for the macrophytes) I can not find this process to add. maximum biomass for macrophyt submerged 01 & 02 but no maximum biomass for the macrophytes.
I know I have a lot of question and you are so helpful and I really appreciate it.
I attached my new lsp file.
MaxMacro has to decide how much biomass can exist at a particular location for all the macrophytes at once. Therefore it can not be used on each macrophyte separately (like with the growth process). The habitat suitability index can be used to indicate if a particular location is suitable for the macrophyte. For instance: macrophyte that need to attach to a rocky bottom won't hold in a region where the bottom consists of sand or silt.
Thanks a lot for helping me. I am a little confuse because I do not have the MaxMacro in my extra process. I can just tick Maximum biomass as an editable. I attached the screenshot. As well as segment number that you ask me. they both do not have default value or any process to calculate them so I just tick them as editable and edit them in the process parameter section.
I think maybe I missed some thing but I do not know what is it.
What version of Delft3D are you using? (In principle you could use the latest version of the process configuration files - proc_def.dat/proc_def.def and I could send them to you but there is a small caveat that I need to check)
I am using Delft3D 4.02.03. I will upgrade my source.
Thanks for everything