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[lei2019]

relevant topic: When reading a data file of 23GB by Fluent, Error: Invalid section id .....

Thank you Kanade and Rob. The module I use is "module load ansys/fluids_19.2". So the version is R19.2.

When I can't read it in 40 cores, somehow I can read dat.gz file with 6GB in 80 cores. But I can't request more CPU resource; 40 cores to run two weeks is my quota. Now I have to run the case day by day in order to request 80 cores.

The case has run on HPC, and files are saved on HPC; I think it is local drive.

Since I doing coal combustion with DPM model, the number of particles at flow time 1.6 s is about 15 million. each time step, 9400 particles are injected into the burner. it is one of the reasons that file size keeps growing.

[Rahul Kumar]

Hello,
To better assist you, can you please give us information on solution methods that you are using? These are stability warnings, please try reducing the URF values.

[lei2019]

Hi,
This is LES simulation of coal combustion, by species model, Discrete phase model, DO radiation; the particle number reaches up to 50 million;
using 2021R1, automatic Metis partitioning, single precision;
using two udf file to define coal properties wsg for radiation and define ash volume after coal burnout, which should be no effect on divergence and this error.
For coal combustion simulation, I adjusted URF of DPS from 0.1 to 0.9 after the simulation is stable. but after running for about 3 seconds flow through time, it became unstable again.
After I rerun the case, it also encounters problem of corrupted unsorted chunks and continuity can't converge well. I use 120 cores, OS system:
previously we encounter crash problem because the data file is too big 15GB. I use H5 file format now. a previous post has been linked to this post.
I can try to use lower URF of DPS, but I still need to increase it to 0.9 and want the simulation be stable at 0.9.
the error log file and the fluent simulation output have been attached.
Please help.

Thank you.

[lei2019]

I think I may find the reason for the divergence and error. I previously set DPM iteration interval 300, which seem too big for the simulation and leads to 10,000 particle escape; when I reduce it to 30, escape particle number reducing.

[lei2019]

Hi RK I run the same case with 120 cores, except the URF DPS = 0.5 (previous one is 0.9). So I thin URF of DPS may be not the issue. I will keep running this case to check whether the DPM iteration interval cause this. Thank you.
Lei


myid (87): Fatal signal raised sig = SIGSEGV
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0() [0x266a6dc]
/lib64/libpthread.so.0(+0xf5d0) [0x7f9ae923b5d0]
/lib64/libc.so.6(+0x39acd) [0x7f9adc72cacd]
/lib64/libc.so.6(+0x39bb7) [0x7f9adc72cbb7]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0() [0x26677fe]
/lib64/libpthread.so.0(+0xf5d0) [0x7f9ae923b5d0]
/lib64/libc.so.6(__sched_yield+0x7) [0x7f9adc7d5d47]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/mpi/lnamd64/intel/lib/libmpi.so.12(PMPIDI_CH3I_Progress+0x230e) [0x7f9ada4a3b4e]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/mpi/lnamd64/intel/lib/libmpi.so.12(+0x29cc63) [0x7f9ada607c63]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/mpi/lnamd64/intel/lib/libmpi.so.12(+0x1108d4) [0x7f9ada47b8d4]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/mpi/lnamd64/intel/lib/libmpi.so.12(+0x10ff40) [0x7f9ada47af40]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/mpi/lnamd64/intel/lib/libmpi.so.12(MPI_Barrier+0x63d) [0x7f9ada47eedd]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/mpi_wrapper/lnamd64/intel/libmpi_wrapper.so(WMPI_Barrier+0x4d) [0x7f9aebee1c88]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/lnamd64/mpi/shared/libmport.so(mpt_mpi_gsync+0x16) [0x7f9aec1923f9]
/shared/software/ansys/v211/fluent/fluent21.1.0/multiport/lnamd64/mpi/shared/libmport.so(MPT_gsync+0xfd) [0x7f9aec13fcfe]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0(par_fopen+0x15c) [0x1d2460c]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0() [0x229ec03]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0(eval+0x1f6) [0x26823c6]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0(PRF_Command_Start+0x1327) [0x683a47]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0(PRF_Node_repl+0x2e) [0x684d9e]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0(fluent_main+0x3dd) [0x69b6dd]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0(main+0x59) [0x6acc39]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f9adc7153d5]
/shared/software/ansys/v211/fluent/fluent21.1.0/lnamd64/3d_node/fluent_mpi.21.1.0() [0x592111]