Heat transport parameters

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Jaume Tormo
Posts: 2
Joined: Thu Apr 04, 2019 8:26 am
Location: Spain

Heat transport parameters

Post by Jaume Tormo » Thu Apr 04, 2019 10:16 am

Hello,
My name is Jaume Tormo, I'm new in the forum. First of all thank you very much for the help you provide.

I’m trying to simulate soil temperature using Hydrus 1D. But I am confused with some heat transport parameters. I have tried program help, beginners tutorial (Example 8 ) and the Hydrus manual but I am still confused.
Lets say I need to simulate one month of soil temperature. I have data on daily mean, maximum and minimum atmospheric temperature hence I can calculate temperature amplitude for each day.
In the “Heat transport parameters” window, what temperature amplitude do I need to provide? An average of the daily amplitude? Or do I need to provide this value for each day in the “Time Variable Boundary Conditions” window? If I provide the amplitude for each day at the “Time Variable Boundary Conditions” window, then what do I need to provide at the Temperature Amplitude box in the “Heat Transport Parameters” window? I understand (Based on the program help “Note that Amplitude should be zero, when detailed temperature values are provided”) that I must write 0 is it correct?
Regarding “Interval for one temperature cycle”. If I am providing data on the “Time Variable Boundary Conditions” window in a daily basis then, do I need to provide here 1 day or one month because I am simulating 1 month.
Regarding “Heat Transport Boundary Conditions” window, where could I find what the options mean? I mean the upper boundary of my soil is in contact with the atmosphere which option describes this case? In other words what is the difference between “Temperature BC” and “Heat flux BC”? I have tried the Hydrus program help, the manual and the tutorial book but I could not find that, any clue where can I find it?

Thank you very much.

Jaume.

Jirka
Posts: 4651
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Heat transport parameters

Post by Jirka » Thu Apr 04, 2019 4:42 pm

1. "TTop" and "Apl" values from the "Time-Variable Boundary Conditions" window are used when time-variable boundary conditions are applied at the surface. "Temperature Amplitude" value from the "Heat Transport Parameters" window is used otherwise (when a constant flow BC is used at the soil surface.
2. The term “Interval for one temperature cycle” seems to be pretty self-explanatory. It is one day when you use diurnal changes and one year when annual changes.
3. The difference between “Temperature BC” and “Heat flux BC”: See Chapter 4.3 in the manual.

J.

Jaume Tormo
Posts: 2
Joined: Thu Apr 04, 2019 8:26 am
Location: Spain

Re: Heat transport parameters

Post by Jaume Tormo » Mon Apr 15, 2019 4:23 pm

Thank you very much.

Jaume.

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