Moving nests for multiple domains with preset moves

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fluids2020
Posts: 2
Joined: Mon Nov 30, 2020 1:46 am

Moving nests for multiple domains with preset moves

Post by fluids2020 » Mon Nov 30, 2020 2:12 am

Hello,

I have three domains with two nests and I want to move the two nests with preset moves. I tested this with the settings in the namelist shown below. I am using executables from the compile option for preset moves. The problem is I can only get the innermost domain (domain 3) to move with these settings. Domain 2 does not move. In fact, when I *only* try to move domain 2, it still does not move. There should be plenty of room for domain 2 to move. What am I missing here?

Thanks.


input_from_file = .true.,.false.,.false.,
max_dom = 3,
grid_id = 1, 2, 3,
parent_id = 0, 1, 2,
num_moves = 2
move_id = 2,3
move_interval = 10,10
move_cd_x = 1,1
move_cd_y = 1,1

Ming Chen
Posts: 1455
Joined: Mon Apr 23, 2018 9:42 pm

Re: Moving nests for multiple domains with preset moves

Post by Ming Chen » Mon Nov 30, 2020 10:55 pm

There is a logic in the moving of the nested domains. Basically, the innermost domain moves first. Only when it reaches close enough to its parent domain, can the parent domain be forced to move. This is for automatic nest moving. I am not sure whether the preset nest moving follows the same rule. I will check get back to you.
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Ming Chen
Posts: 1455
Joined: Mon Apr 23, 2018 9:42 pm

Re: Moving nests for multiple domains with preset moves

Post by Ming Chen » Tue Dec 01, 2020 7:25 pm

I have two suggestions:

(1) please test the following strategy with preset move:
try to force domain 2 to move closely with domain 3 by setting your domain 3 large enough so that the boundaries are 2 grid points within the corral_dist (see example below). Note that the domain 3 starts at the parent domain's (33,33) point, and corral_dist is set to be 31. This setting would allow domain 3 to push domain 2 to move almost together.

Here is an example for automatic move:

e_we = 320, 133, 199,
e_sn = 210, 133, 199,
grid_id = 1, 2, 3,
i_parent_start = 1, 177, 33,
j_parent_start = 1, 40, 33,
corral_dist = 8, 8, 31,

(2) Please set num_moves = 50, then try again.
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fluids2020
Posts: 2
Joined: Mon Nov 30, 2020 1:46 am

Re: Moving nests for multiple domains with preset moves

Post by fluids2020 » Thu Dec 10, 2020 7:34 pm

Hi Ming,

Thanks for your response and sorry for the delay. I tested what you suggested by initializing domain 3 close to the edge of domain 2 and then giving domain 3 a few preset moves towards the edge of domain 2. This did allow domain 2 to move once domain 3 got close enough. However, I did not find that the "corral_dist" setting played a role because I think that is a setting only for the vortex following option. When I set this parameter to some larger number (say 15), the preset moves ignored it. I am not sure how wide the edges are for preset moves (I think the default for corral_dist is 8, but again it ignores this setting). At least I know how domain 2 can move now and I will test my production run to see if this will continue to work.

Ming Chen
Posts: 1455
Joined: Mon Apr 23, 2018 9:42 pm

Re: Moving nests for multiple domains with preset moves

Post by Ming Chen » Tue Dec 15, 2020 3:07 am

You are right that corral_dist is an option only for automatic moving. The sample I provided is for automatic moving. What I try to confirm is that, for both preset and automatic moving, D02 can only move when D03 is close enough to the boundary of its parent domain.
I actually don't recommend running the preset moving, because it is hard to specify the required information for this option. Automatic moving can well describe the system and can be easily handled, which is the main reason we usually recommend this option.
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