Search found 23 matches

by logvinov
Thu Sep 17, 2009 7:55 pm
Forum: ROMS Discussion
Topic: Bottom boundary condition on the temperature
Replies: 0
Views: 628

Bottom boundary condition on the temperature

Hello,
I have a quick question. Could anybody tell me what is the bottom boundary condition on temperature?
I use ana_btflux.h. How does ROMS is it? Is it btflux=Kv*dT/dz or btflux=Kn*dT/dn, where n is normal to the bottom boundary?

Thanks a lot,
Evgeny
by logvinov
Mon Jun 16, 2008 2:08 pm
Forum: ROMS Problems
Topic: Diagnostics for temperature
Replies: 2
Views: 1196

Re: Diagnostics for temperature

Thanks John,

It helps a lot.
by logvinov
Fri Jun 13, 2008 2:36 am
Forum: ROMS Problems
Topic: Diagnostics for temperature
Replies: 2
Views: 1196

Diagnostics for temperature

Hi All, I am having some trouble with using term diagnostics in the equation for temperature. In particular vertical and horizontal advection terms looks pretty suspicious. I did the estimates for the terms just "by hand"- using temperature and velocity fields. And the estimates for all the terms bu...
by logvinov
Wed Mar 26, 2008 1:05 am
Forum: ROMS Discussion
Topic: Bottom boundary condition: no slip
Replies: 4
Views: 2233

Hey Jessica,
Glad to see you here!

As I understand you did this:
#define UV_LDRAG

Try this to get no slip:
RDRG == 5.0d-02

Works for my application.

All the best,
Evgeny
by logvinov
Mon Feb 25, 2008 11:53 pm
Forum: ROMS Discussion
Topic: Bottom heat flux
Replies: 0
Views: 844

Bottom heat flux

Hi All, I am simulating stratified flow in the channel. I want to maintain a steady linear stratification (temperature). To do so I use ana_btflux and ana_stflux. In flat bottom case it worked well I just set them to some appropriate (the same for both) value, depending on the desirable intensity of...
by logvinov
Mon Feb 25, 2008 7:55 pm
Forum: ROMS Discussion
Topic: vertical mixing
Replies: 3
Views: 1718

Hi Kate, Thanks for your reply. I am using ana_vmix. And so far I keep constant value of AKt everywhere in the domain. T do that to keep theory simple. And it was good enough for the flat bottom domain. Now I added sloping bottom to the problem. Due to the downwelling favorable wind advection of the...
by logvinov
Wed Feb 20, 2008 6:02 pm
Forum: ROMS Discussion
Topic: vertical mixing
Replies: 3
Views: 1718

vertical mixing

Hi All, I am looking at the case of downwelling favorable wind driven flow in the domain with the sloping bottom. This leads to an advection of lighter fluid beneath heavier fluid. Could anybody tell me if there are any special tools in ROMS to intensify mixing in regions of unstable stratification?...
by logvinov
Fri Jan 25, 2008 10:26 pm
Forum: ROMS Discussion
Topic: Surface boundary condition
Replies: 5
Views: 2708

The problem was in using

#define SPLINES
#define UV_SADVECTION

I terned them off and now everything is working
by logvinov
Fri Jan 18, 2008 7:21 pm
Forum: ROMS Discussion
Topic: Surface boundary condition
Replies: 5
Views: 2708

The resolution is pretty hight already. It has 5-6 points in Ekman layer, so I don't think there should be a problem with resolution. I'll try the bigger values of Vertical mixing
by logvinov
Fri Jan 18, 2008 1:49 am
Forum: ROMS Discussion
Topic: Surface boundary condition
Replies: 5
Views: 2708

Hi Alexander, Thanks a lot for your reply! Yep, Ekman layer is there, but as you said it is 4.5m. And indeed there is a significant correction on the field in the Ekman layer, which actually tends to go to the right value of du/dz (that would satisfy a stress condition). But We see a very sharp chan...
by logvinov
Thu Jan 17, 2008 3:37 pm
Forum: ROMS Discussion
Topic: Surface boundary condition
Replies: 5
Views: 2708

Surface boundary condition

Hi all, I have a question about surface boundary condition. I run application with uniform wind in x-direction sustr=5e-8 and with a constant value of Akv=1e-3. When I checked the output the stress condition (sustr=Akv*du/dz) didn't work! Value in the output (Akv*du/dz) is ~15% less. What is especia...
by logvinov
Thu Jan 10, 2008 3:10 pm
Forum: ROMS Information
Topic: What is the output of DIAGNOSTICS_TS/UV?
Replies: 6
Views: 4606

What is the output of DIAGNOSTICS_TS/UV?

Hi all, I have a question about the dia.nc file. What kind of terms does it contain? Are those terms have simply form of the terms in N-S equations or something more complicated? u_accel u_hadv u_vadv u_cor u_prsgrd u_hvisc u_vvisc temp_rate temp_hadv temp_vadv temp_hdiff Could you tell me if it is ...
by logvinov
Fri Jan 04, 2008 5:48 am
Forum: ROMS Discussion
Topic: vertical mixing coefficient for ana_vmix
Replies: 2
Views: 1357

Thanks a lot John!
by logvinov
Fri Jan 04, 2008 1:36 am
Forum: ROMS Discussion
Topic: vertical mixing coefficient for ana_vmix
Replies: 2
Views: 1357

vertical mixing coefficient for ana_vmix

Hi all, In my problem I use ANA_VMIX, where I define AKv and AKt to be equal to constant AKv_bak=1e-3 and AKt_bak=1e-3 respectively. if defined EKMAN_WALL DO k=1,N(ng)-1 DO j=JstrR,JendR DO i=IstrR,IendR Akv(i,j,k)=Akv_bak(ng) END DO END DO END DO if defined EKMAN_WALL DO k=1,N(ng)-1 DO j=JstrR,Jend...
by logvinov
Wed Jan 02, 2008 9:35 pm
Forum: ROMS Discussion
Topic: Advection and diffusion in buoyancy equation
Replies: 0
Views: 1152

Advection and diffusion in buoyancy equation

Hi All, Could somebody explain how the advection and diffusion of temperature calculated? TS_U3HADVECTION TS_C4VADVECTION? I am trying to simulate a case in which vertical advection of temperature is balanced by horizontal diffusion of temperature. (with background linear stratification maintained b...
by logvinov
Wed Nov 14, 2007 4:44 am
Forum: ROMS Discussion
Topic: 2D case
Replies: 1
Views: 1288

2D case

Hello all,

Could you tell me is it possible to run ROMS for 2D applications? So consider the problem only in z(vertical) and y(horizontal) coordinates. I am trying to do that to avoid instabilities.

Thanks a lot,
Evgeny
by logvinov
Thu Sep 27, 2007 8:11 pm
Forum: ROMS Usage
Topic: Numerical error
Replies: 3
Views: 1627

Thanks a lot for the suggestions!

Now it does work when switched to
#define MIX_S_UV
by logvinov
Wed Sep 26, 2007 3:53 pm
Forum: ROMS Usage
Topic: Numerical error
Replies: 3
Views: 1627

Numerical error

Hi All, I consider a simple case of wind driven flow in the channel (Wall and periodic BCs) with sloping bottom (cross the channel). So there should be no variation in the flow along the channel. But the output of the run demonstrate significant variations in the flow along the channel. I believe th...
by logvinov
Thu Aug 30, 2007 6:27 pm
Forum: ROMS Discussion
Topic: Sloping bottom
Replies: 2
Views: 1404

just a quick check - i assume you did a pcolor on the bottom bathy and the slope is in the right direction? how did you add the slope? is it a tiling issue in the way you may have set ana grid ?? (these are just a few quick guesses). Thanks for your reply. Yep I did pcolor and the slope is in a rig...
by logvinov
Thu Aug 30, 2007 4:57 pm
Forum: ROMS Discussion
Topic: Sloping bottom
Replies: 2
Views: 1404

Sloping bottom

Hello, I am using ROMS for running very simple model. Uniform wind stress on the top is from West to East direction. No stratification. BCs: Wall for North and South Periodic for E-W For flat bottom case I got good output (Ekman top and bottom flow, interior flow in the direction of the wind). But w...
by logvinov
Sun May 13, 2007 3:42 pm
Forum: ROMS Discussion
Topic: Vertical velocty at the wall (WALL boundary condition)
Replies: 2
Views: 1470

Vertical velocty at the wall (WALL boundary condition)

Hello, I have a question about the WALL boundary condition. I consider 3D rectangular basin with uniform wind forcing on the top in E-W direction. I put periodic boundary conditions in E-W direction and WALL boundary conditions on the North and South. So I put no slip condition GAMMA2 = -1.0d0 in th...
by logvinov
Thu Apr 05, 2007 6:15 pm
Forum: ROMS Discussion
Topic: boundary condition
Replies: 1
Views: 1506

boundary condition

Hi,
I have a question about periodic boundary conditions.
In cppdefs.h I defined EW_PERIODIC. And I got that omega goes to 0 at the boundaries. And far from the boundaies it is non0. Could you explain what kind of boundary condition is EW_PERIODIC?

Thanks a lot,
Evgeny
by logvinov
Wed Mar 07, 2007 9:11 pm
Forum: ROMS Information
Topic: Wall boundary condition
Replies: 1
Views: 1676

Wall boundary condition

Hi all,
I have a simple question. Can somebody tell me what kind of boundary condition is WALL (in cppdfs)? In particular what kind of bc it sets for a velocity parallel to the wall?

Thanks a lot,
Evgeny