Floating point error! - Overflow

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Mafer
Posts: 5
Joined: Sun Jul 22, 2012 3:59 pm

Post by Mafer » Mon Jul 23, 2012 8:13 pm

respose:
1. precipitation = 11.54 m/d

2. theta r = 0.024
Theta s = 0.264
alpha = 5.039 1/m
n = 4.0611
Ks = 0.0864 m/d

3. -0.405
4. En surface, apply Line-FE-Size, S = 1 m, and the rest of domain TS = 5 m

Jirka
Posts: 4801
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Post by Jirka » Mon Jul 23, 2012 8:41 pm

This will never work.
1. Precipitation rate seems unrealistically high
2. These are strange soil hydraulic properties. On the one hand, the n value is very high, which is common for coarse textured soils, on the other hand the saturated hydraulic conductivity is quite low - only 8 cm/d (note that this is three orders of magnitude smaller than your precipitation flux).
4. For the soil with n this high, you will need to have vertical discretization on the order of cm (not m), as indicated the file that I recommended you to read.

J.

Mafer
Posts: 5
Joined: Sun Jul 22, 2012 3:59 pm

Post by Mafer » Wed Jul 25, 2012 12:08 pm

Thank you for your help.

the parameters were obtained by suction and permeability tests constant load. But because of the inconsistencies already decided to replace them with what was observed in the field, and this corresponds to a coarse material.

the question now is, as income a column of water on the ground I want to see if it is not constant in water, but the product of maximum rainfall event?? for this I was using the weather condition with the total rainfall as input. Another option I can use?

Jirka
Posts: 4801
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Post by Jirka » Wed Jul 25, 2012 2:25 pm

I do not know. HYDRUS-2D does not allow accumulation of water at the soil surface (which is what I understand you refer to by "column of water"). Any excess water (precipitation over infiltration capacity) is assumed to be immediately removed by surface runoff.

J.

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