Search found 10 matches

by chenry
14 Mar 2024, 12:56
Forum: External tools
Topic: Problem reading in netcdf file at higher resolution
Replies: 4
Views: 62

Re: Problem reading in netcdf file at higher resolution

Just a quick update on this. I have slightly reduced the size of the domain and am no longer having problems with the GridDataReader. This doesn't explain why the GridDataReader didn't work with the previous domain at a higher res, but at least there is a solution to the problem.

-C
by chenry
07 Mar 2024, 15:26
Forum: External tools
Topic: Problem reading in netcdf file at higher resolution
Replies: 4
Views: 62

Re: Problem reading in netcdf file at higher resolution

Hi Peter, Thanks for your reply. The error is occurring when reading in the data using the netcdf reader (GridDataReader). The last lines with a verbosity of 30 are: 0: GridDataReader: Found 1 dimensional coordinate variable > x < : 1 0: GridDataReader: Found dimension > x < with id 1 and size 311 0...
by chenry
07 Mar 2024, 00:04
Forum: External tools
Topic: Problem reading in netcdf file at higher resolution
Replies: 4
Views: 62

Problem reading in netcdf file at higher resolution

Hi, I'm having some trouble reading in a netcdf file with an increased mesh resolution, causing a seg fault and stopping at the line: GridDataReader: Performing interpolation for variable: vx My simulation runs fine with a mesh resolution of 500 m, but an increase to 450 m causes this seg fault. Is ...
by chenry
31 Oct 2023, 13:18
Forum: External tools
Topic: Mesh refinement and boundary tags
Replies: 3
Views: 453

Re: Mesh refinement and boundary tags

Many thanks for your reply — that is indeed a much cleaner way to convert to an msh file. Unfortunately, I am still having issues with the boundary tags, however. It seems that they are dropped during mesh refinement at some point which can be seen in the fourth column under $Elements in the msh fil...
by chenry
30 Oct 2023, 23:52
Forum: External tools
Topic: Mesh refinement and boundary tags
Replies: 3
Views: 453

Mesh refinement and boundary tags

Hi all, I’ve been using the MMG2DSolver to refine a mesh in a given area and this has worked perfectly. I’m now comparing my Elmer/Ice simulations with another model (icepack) and would like to use the same refined mesh which should be in an .msh format with boundary tags. After using the MMG2DSolve...
by chenry
09 Aug 2022, 15:24
Forum: Elmer/Ice
Topic: Temperature solver diverges at small timesteps
Replies: 3
Views: 1641

Re: Temperature solver diverges at small timesteps

Hi Peter, Thanks very much for your suggestion. I ran simulations over night with Neumann rather than Dirichlet conditions and am now longer having issues with divergence. A note to anyone else having these issues: a small time step was necessary when using Neumann boundary conditions. A large time ...
by chenry
08 Aug 2022, 12:40
Forum: Elmer/Ice
Topic: Temperature solver diverges at small timesteps
Replies: 3
Views: 1641

Temperature solver diverges at small timesteps

Dear all, I've been running thermo-mechanically coupled simulations of an ice rise and am having trouble with the temperature solver. The solver diverges even at small time steps (0.01 yrs) and I think high temperature gradients at the grounding line may be the cause. Here's a brief description of t...
by chenry
19 Jul 2021, 11:04
Forum: Elmer/Ice
Topic: Numerical instabilities (spikes in the ice surface) at grounding line
Replies: 4
Views: 6421

Re: Numerical instabilities (spikes in the ice surface) at grounding line

Thank you for your help, Olivier. I was able to fix the problem in the end by avoiding a BMB discontinuity at the grounding line.

All the best,

Clara
by chenry
24 Mar 2021, 13:44
Forum: Elmer/Ice
Topic: Numerical instabilities (spikes in the ice surface) at grounding line
Replies: 4
Views: 6421

Re: Numerical instabilities (spikes in the ice surface) at grounding line

Hi Olivier, Thanks for your reply. I am running a full Stokes 3D simulation and the grounding line in question is in a collision zone. The basal friction coefficient is set to 7.624e7 and the basal melt rate is dependent on the ice thickness and distance from the GL (Favier et al., 2016). Our curren...
by chenry
24 Mar 2021, 12:17
Forum: Elmer/Ice
Topic: Numerical instabilities (spikes in the ice surface) at grounding line
Replies: 4
Views: 6421

Numerical instabilities (spikes in the ice surface) at grounding line

I'm running a simulation with a transient grounding line and am observing numerical instabilities in the form of spikes on the upper ice surface and inverted spikes on the lower ice surface. Has anyone else experienced this and has a solution to fix these numerical instabilities?