2020-01-20 MercuryDPM Meeting

1. CG functions for volume coupling
2. Chute system: coupling Marix's mu(I) and DPM

actions after time step issue fixed in Mitchel's local code, will be committed soon

Update: coupling works if two steps with Re=0 is done

FreeCooling still fails with two periodic boundaries

• Thomas Weinhart will look at it
  

Trunk USER/Paolo directory currently fails

• Anthony Thornton will check and delete the directory
  

Hope that you are doing well.

ISSMGE’s TC105 Geomechnics from Micro to Macro chaired by me is running a DEM round robin test.

https://www.issmge.org/news/tc105-dem-round-robin-test

Can you pass this news to our Powders and Grains colleagues, if possible?

Thanks in advance.

Best wishes,

• Hongyang Cheng takes lead, will contact the organisers.

Update: Hongyang contacted the organisers. He will put the description of the test problem on Jira. They will publish the results without linking the codes to the outputs It will be angle of repose measurement for multisphere particles.

• Hongyang will make a JIRA job for this problem.
• @all: We need a volunteer to run the test problem

Update: Anthony volunteered.

• Thomas Weinhart will do it now.

• Luca
  • When configuring cmake I get the first error, concerning a CMP0057 error.
    I get rid of it by editing the file Source/CmakeModules/MercuryDocumentation.cmake and commenting the first line (cmake_policy(SET CMP0057 NEW)).
• DPM issues.docx

Now the docker is tested on Windows(Enterpirse, with Hyper-V activated), Mac(10.15) and XUbuntu(18.04) with the possibility of sharing the files between the container and the host machine.

The draft instruction is on the confluence page: "Docker Instructions", please take a look and let me know if you have trouble in following that instruction.

Could someone download docker on his Windows(Professional) system and test it?

Hao needs to check if there is a possibility to make docker works also on Windows(Home).

If this is settled, we could use it for the MercuryDPM course.

1-way coupled code is approx 4000 faster but does not work for non-refinables elements as it needs the extra data

Hao did the test on 4000 particles with new code, the Oomph-part is indeed much faster than the older version, this reduces the total simulation time by approx. 20%.

However, it seems somewhere else is getting heavier and the new run compare to the old run is actually longer. Hao checked with Mitchel on both old and new implementations

and found out the time cost difference on the locate_zeta function in pressure gradient. Think of updating coupling force not every Mercury Timestep to reduce the run time.

• Anthony Thornton and Thomas Weinhart will look at it with Mitchel Post on Wednesday
  

Jinja or Jinja2

Do we want to add a python interface to MercuryDPM in the future?

Would be useful to use in combination with GrainLearning.

We also have the Mercury command line interface, but that cannot pass functions.

Starts April 20; first week we give the MercuryDPM courses (April 27-May 22)

• Anthony Thornton Book Vrijhof or Performance Factory

There is a student from Erlangen (attanded DEM8) who might be interested in writing this interface in the MercuryMonth [from Hao]

• h.shi-1 remind him

Youetta made a video:

• h.shi-1 Final Tweaks still missing, remind Youetta

Documentation needed for:

• Advanced tutorials (written by the developers)
• New tutorials
• Interaction::computeNormalForce

Julius wants to use MPIIO for parallel output.

Julius showed profile of Mercury showing that most time is spent in computeForces(p,q). mcount, output is removed. virtual functions are still costly