Numerical convergence problem

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rajsekhar
Posts: 17
Joined: Thu Nov 29, 2018 5:58 am
Location: India

Numerical convergence problem

Post by rajsekhar » Tue Sep 03, 2019 7:07 pm

Dear Sir,

Sometimes HYDRUS does not stop on its own after showing the error i.e. numerical solution not converged! even if I have not checked the option Hit enter at the end. Please help me regarding this issue.

Jirka
Posts: 4733
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Numerical convergence problem

Post by Jirka » Tue Sep 03, 2019 10:47 pm

Since the Richards equation is a highly nonlinear equation, there is always a chance that the numerical solution will not converge. However, for physically realistic problems, this should be rather rate. J.

rajsekhar
Posts: 17
Joined: Thu Nov 29, 2018 5:58 am
Location: India

Re: Numerical convergence problem

Post by rajsekhar » Wed Sep 04, 2019 5:30 am

Dear Sir,

My issue is not with the non-convergence of the simulation, the problem is sometimes it does not stops on its own after showing the error, I need to forced stop it. I am attaching the image which shows the problem I am facing.

Thank you
K Rajsekhar
Attachments
HYDRUS image.JPG
HYDRUS image.JPG (67.38 KiB) Viewed 645 times

Jirka
Posts: 4733
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Numerical convergence problem

Post by Jirka » Sat Sep 07, 2019 11:49 am

I would need to see your project. However, I would not have time to look at it until the end of September as I’m currently traveling in Himachal Pradesh, India. J.

rajsekhar
Posts: 17
Joined: Thu Nov 29, 2018 5:58 am
Location: India

Re: Numerical convergence problem

Post by rajsekhar » Tue Sep 10, 2019 7:17 pm

Dear Sir,

I have attached my project, please check it. And have a happy stay in INDIA. If you have time do please visit IISc Bangalore. I am doing PhD under prof. Sekhar Muddu in IISc. I guess you visited IISc long back for a short course on HYDRUS.
Attachments
daily.rar
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rajsekhar
Posts: 17
Joined: Thu Nov 29, 2018 5:58 am
Location: India

Re: Numerical convergence problem

Post by rajsekhar » Wed Sep 11, 2019 11:46 am

Dear Sir,

Please check this attachment, in the earlier attachment forgot to add some files.
Attachments
daily.rar
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rajsekhar
Posts: 17
Joined: Thu Nov 29, 2018 5:58 am
Location: India

Re: Numerical convergence problem

Post by rajsekhar » Fri Sep 13, 2019 5:36 am

Dear Sir,

what I realized is when the head is less than -10000000 the above problem arises i.e. hydrus doesnot stop after showing the error. Don't know how to tackle this issue.

rajsekhar
Posts: 17
Joined: Thu Nov 29, 2018 5:58 am
Location: India

Re: Numerical convergence problem

Post by rajsekhar » Fri Sep 13, 2019 6:29 am

Dear Sir,

Issue is resolved. Actually the problem was with hCritA, as I fixed the hCritA to 15000 and for n=1.05 h values are around 10e+20.

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