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Hi

In order to model sea water warming due to coastal power station outflow, I have introduced the subroutines METEO and THERMAL following useful comments from this forum. Nevertheless, I keep on failing with the module EXCHANGE_WITH_ATMOSPHERE. Indeed, I do not understand where this module is being called.

I put attached the fortran file.

Any help would be much appreciated.
Thanks

Claire

Hi

A global remark about your fortran file.
A module should not figure in a fortran file! If you wants to modify a module, you should modify it in the sources and make a full compilation of the system.

Not sure it will be sufficient to solve your problem but it's necessary in order to investigate deeper

Regards

Hi

Thanks for your remark. I know what you mean and will try to sort that out.

Regards
Claire

Hi

I finally manage to compile the all system including the module exchange_with_atmosphere and to simulate water evaporation.
Nevertheless, it seems that temperature aspects (water warming due to solar and atmospheric radiation + heat loss due to evaporation) are not included.

Can you please tell me which subroutine must be amended to calculate and include heat fluxes?

Any help would be much appreciated.
Thanks
Claire

Hi Claire,

In the EXCHANGE_WITH_ATMOSPHERE module:
- water warming due to solar radiation is calculated by SOLRAD subroutine,
- atmospheric radiation is calculated by SHORTRAD subroutine,
- heat loss due to evaporation is calculated by EVAPO subroutine.

All these subroutines have to be called by BORD3D subroutine to compute the boundary conditions.

Hope this helps,

Chi-Tuan

Hi Chi-Tuan and thanks you very much for you reply!

Yes, I agree with you: I can compile and run the module when I call its subroutines in BORD3D subroutine. I also had to declare in the BORD3D subroutine all the new variables used in the module.

I have run some sensitivity analysis to check if it is running fine:
*I compared SOLRAD values in runs during night or day. SOLRAD was equal to zero during the night and equal to about 800 W/m2 at midday (in clear sky conditions). These orders of magnitude seem correct.
*Atmosphere radiation and water radiation were higher when air and water temperature were warmer respectively. So these radiations seem correctly computed with correct orders of magnitude.
*I also managed to model sea evaporation in "extrem" conditions (high wind speed, no cloud, warm water temperature, ...). Nevertheless, the cooling of water during evaporation was not simulated so I assume that latent heat is not taken into account even if it is calculated (FLUX_EVAP).
*As I could not warm up water temperature with solar radiation, I assume sensible heat is calculated (FLUX_SENS) but is not taken into account neither.

As I need to model these processes, I tried to amend the code.
The code modifications I have done so far in BORD3D subroutine are:
*to calculate the total radiation that go through the free surface (using telemac variables, I find for the total radiation: RAY_TOTAL = RAY_SOL + RAY_ATM - RAY_EAU - FLUX_EVAP - FLUX_SENS)
*to calculate the absorption of heat for each layer (absorption decreases exponentionaly with water depth)

Then I plan to:
*calculate in BORD3D the temperature variations due to heat flux in each layer
*introduce these temperature variations in the code.

As rain temperature is taken into account in the latest version of Telemac3d, I guess I have to include temperature variations due to heat flux in the subroutines that take account of rain temperature.
So I selected all the subroutines using the variable TRAIN (for rain temperature). I believe I have to amend the following subroutines:
*tvf.f
*cvdftr.f
*tracvf.f
*cvtrvf_pos.f
*cvdf3d.f
*diff3d.f
*murd3d_pos.f

1)Can you please confirm that the latent and sensible heat are not computed in the current Telemac3d version?
2) Can you please tell me if what I intend to do seems correct and if the subroutines I list above are the one that have to be amended to take account of temperature aspects?

I hope this post is clear enough...

Many thanks if you have any comments on my method or answers to my questions.

Claire

Hi everyone,

I'll start to work in a similar problem, study the impact of a power station outflow in a bay. I was looking for information about what I'm able to do with TELEMAC and I found this interesting post.

Any answer to Claire's questions?

Claire, did you try your modifications?

Thanks a lot!
Pablo

Hi

No, I have not completed my modifications yet. I am currently working on different project but will have to complete my modifications in the future.

I found the method and formulations to calculate the heat exchange from litterature and Delft3d manual.

Hope that helps
Claire

Hi

Few years back I was using Telemac vp.1 to simulate a simular problem by that time a simplified equation based on the temperature of water and wind velocity was used for the heat exchange with the athmosphere. I know that in the current version there is a new subroutine Exchange with the athmosphere that uses the Boltzmann equation.
Does any of you used this new subroutine?? if yes could you please share the changes that you make in the case file and fortran file. Also in which format should the solar radiation, atmospheric pressure, cloud cover, relative humidity, etc be input??
Any help, comments documentation is appreciated

Thanks

Viviana