Fatal error in function StopAtBoundary and in function 996

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jdaniels
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Joined: Wed May 26, 2021 6:55 pm
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Fatal error in function StopAtBoundary and in function 996

Post by jdaniels » Wed May 26, 2021 7:06 pm

Hi all,

I'm trying to model a 3-region slab in z, by using three cuboids and reflective boundary conditions in x and y.

Here's my input file:

Code: Select all

% --- 1D slab in z --------------------------------------

set title '1D_slab_in_z'

% ------------------------------------------------------
% -Geometry
% ------------------------------------------------------

% Define Surfaces
surf 2  cuboid 0.0 10.0  0.0 10.0  0.0 12.95583    % Aqueous layer thickness
surf 3  cuboid 0.0 10.0  0.0 10.0  0.0  7.60000    % Emulsion layer thickness
surf 4  cuboid 0.0 10.0  0.0 10.0  0.0 10.75334    % Organic layer thickness
surf 5  cuboid 0.0 10.0  0.0 10.0  0.0 31.30917    % cuboid surrounding system
surf 21 pz 0.0         % Height of bottom of domain
surf 22 pz 12.95583    % Height of aq layer
surf 23 pz 20.55583    % Height of emulsion layer
surf 24 pz 31.30917    % Height of org layer

% Define Cells
cell 1  1 aqueous  -2    % Aqueous layer
cell 2  2 emulsion -3    % Emulsion layer
cell 3  3 organic  -4    % Organic layer

% put layers into lattice (to get separate x-s data).
lat 401 9 0.0 0.0 1      % aq
     0.0000 1
trans 401 0.0 0.0 0.0
cell 11  0 fill 401 -5 21 -22

lat 402 9 0.0 0.0 1      % em
     0.0000 2
trans 402 0.0 0.0 12.95583
cell 12  0 fill 402 -5 22 -23

lat 403 9 0.0 0.0 1      % org
     0.0000 3
trans 403 0.0 0.0 20.55583
cell 13  0 fill 403 -5 23 -24

cell 21 0 outside 5        % Outside universe


% ------------------------------------------------------
% -Material data:
% ------------------------------------------------------
% what does .03c mean? libraries at 300K
% density -ve so in g/cm^3
% fracions -ve so mass fractions
mat aqueous -1.276 moder lwtr 1001
     1001.03c   -7.750            % H - natural
     7014.03c   -7.812            % N
     8016.03c  -83.890            % O
    94239.03c   -0.514            % Pu-239
    94240.03c   -0.034            % Pu-240
therm lwtr lwe7.00t               % scattering at 293.6K

mat emulsion -1.130
     1001.03c   -8.869            % H
     6000.03c  -25.501            % C
     7014.03c   -5.538            % N
     8016.03c  -56.459            % O
    15031.03c   -1.088            % P
    94239.03c   -2.386            % Pu-239
    94240.03c   -0.159            % Pu-240

mat organic -0.955
     1001.03c  -10.671            % H
     6000.03c  -66.551            % C
     7014.03c   -1.877            % N
     8016.03c  -12.302            % O
    15031.03c   -2.840            % P
    94239.03c   -5.399            % Pu-239
    94240.03c   -0.360            % Pu-240

mat steel -7.93
     6000.03c   -0.00030          % C
    14028.03c   -0.01000          % Si
    15031.03c   -0.00045          % P
    16032.03c   -0.00030          % S
    24052.03c   -0.20000          % Cr
    25055.03c   -0.02000          % Mn
    28058.03c   -0.13000          % Ni
    26056.03c   -0.63895          % Fe

mat air -0.001225
    1001.03c   -0.000000284      % H
    2004.03c   -0.000000724      % He
    6000.03c   -0.000137586      % C
    7014.03c   -0.755187706      % N
    8016.03c   -0.231763751      % O



% ------------------------------------------------------
% -Calculation parameters:
% ------------------------------------------------------

% -URES:
% why have resonance for hydrogen and oxygen?
set ures 1 94239.03c 94240.03c 1001.03c 8016.03c

% -Cross section library file path:
set acelib "/home/greg/Documents/serpent/xsdata/endfb7/sss_endfb7u.xsdata"

% -Set boundary conditions: 1 = vacuum, 2 = reflective, 3 = periodic. Listed as x y z
set bc 2 2 1

% -Set normalisation - total flux = 1.0
set flux 1.0

% -Allow particles to get 'lost'
set lost -1

% --- Group constant generation:
% calculate group constants for universes 0-3
set gcu 0 1 2 3

%  set energy group boundaries - this is two group with the boundary at 0.972eV
set nfg 2 0.972E-6

% --- Neutron population and criticality cycles:
% no. initial neutrons, no. cycles, no. cycles to discard
set pop 100000 400 50

% Define explicit initial fission source
% point sources at t=0
src 1 sp 0.0 0.0 12.0
src 2 sp 0.0 0.0 15.5
src 3 sp 0.0 0.0 18.0
src 4 sp 0.0 0.0 23.0
src 5 sp 0.0 0.0 25.6
src 7 sp 0.0 0.0 30.7

% --- Geometry and mesh plots:
plot 1 500 500
plot 2 500 500
plot 3 500 500
mesh 1 500 500
mesh 2 500 500
mesh 3 500 500
When running serpent, two error messages appear: "Fatal error in function StopAtBoundary" and "Fatal error in function 996". I've had a look through the other posts and can't find anything to help with my problem.

Here's the terminal display from running my input deck:

Code: Select all

Begin calculation on Wed May 26 16:34:38 2021

Reading input file "1D_slab_76mm_emul.0s"...

Checking duplicate input definitions...
OK.

Creating geometry...
OK.

Counting geometry zones...

The geometry consists of 3 levels:

Level 0 size: max 4 zones
Level 1 size: max 1 zones
Level 2 size: max 1 zones

Processing cells...
OK.

Linking materials to geometry...
OK.

Counting cells...
OK.

Processing data for group constant generation:

 - 70 energy groups in micro-group structure
 - 2 energy groups in macro-group structure
 - B1 fundamental mode calculation is not run
 - Group constants generated in 4 universes
 - Discontinuity factors are not calculated
 - Pin-power distributions are not calculated
 - Albedos are not calculated
 - Poison cross sections are not calculated

Plotting geometry:

   0% complete
  33% complete
  67% complete
 100% complete

Reading ACE directory files...
OK.

Adding nuclides in material aqueous...

Nuclide   1001.03c -- hydrogen at 300K (H-1)
Nuclide   7014.03c -- nitrogen 14 at 300K (N-14)
Nuclide   8016.03c -- oxygen 16 at 300K (O-16)
Nuclide  94239.03c -- plutonium 239 at 300K (Pu-239)
Nuclide  94240.03c -- plutonium 240 at 300K (Pu-240)

Adding nuclides in material emulsion...

Nuclide   6000.03c -- natural carbon at 300K (C-nat)
Nuclide  15031.03c -- phosphorus 31 at 300K (P-31)

Adding nuclides in material organic...

Adding thermal scattering data...

Nuclide   lwe7.00t -- hydrogen at 294K (H-1)

Checking data and printing output...
OK.


***** Wed May 26 16:34:39 2021 (seed = 1622043278)
Warning message from function ProcessNuclides:

Minimum photon cross section energy 1.000000E+37 MeV is
above the energy grid minimum 1.000000E-03 MeV.
The energy grid minimum is set to 1.000000E+37 MeV.
Possible changes in energy cutoff cards (warned if any).


***** Wed May 26 16:34:39 2021 (seed = 1622043278)
Warning message from function ProcessNuclides:

Photon energy cutoff 1.000000E-03 MeV is changed to 1.000000E+37.


Generating unionize energy grids...

Adding points:

  1001.03c -- Points added in neutron grid: 252
  1001.03s -- Points added in neutron grid: 91
  6000.03c -- Points added in neutron grid: 873
  7014.03c -- Points added in neutron grid: 1100
  8016.03c -- Points added in neutron grid: 1803
 15031.03c -- Points added in neutron grid: 161
 94239.03c -- Points added in neutron grid: 27251
 94240.03c -- Points added in neutron grid: 17865

Generating unionized energy grid:

 - Unionization performed without grid thinning
   between 1.00E-11 and 20.0 MeV.

 - Final neutron grid size: 49157 points.

 - 2.55 Mb of memory allocated for grid data

OK.

Processing cross sections and ENDF reaction laws...

Nuclide   1001.03c -- hydrogen at 300K (H-1)
Nuclide   1001.03s -- hydrogen at 300K (H-1)
Nuclide   6000.03c -- natural carbon at 300K (C-nat)
Nuclide   7014.03c -- nitrogen 14 at 300K (N-14)
Nuclide   8016.03c -- oxygen 16 at 300K (O-16)
Nuclide  15031.03c -- phosphorus 31 at 300K (P-31)
Nuclide  94239.03c -- plutonium 239 at 300K (Pu-239)
Nuclide  94240.03c -- plutonium 240 at 300K (Pu-240)

SUMMARY -- 8 nuclides included in calculation:

 - 8 transport nuclides
 - Neutron energy cut-offs at 1.00E-11 and 20.0 MeV
 - 160 transport reactions
 - 65 special reactions
 - 21.67 Mb of memory allocated for data
 - 2 nuclides with ures ptable table data:

   94239.03c (from 2.50E-03 to 3.00E-02 MeV)
   94240.03c (from 5.70E-03 to 4.00E-02 MeV)

Processing mesh plots...
OK.

Normalizing compositions and processing mixtures...
OK.

Allocating memory for macroscopic cross section data...
OK.

Allocating memory for particle structures...
OK.

Calculating maximum densities...
OK.

Performing density cut-off...
OK.

Performing ures dilution cut-off with 1.0E-09 threshold...

 - Ures ptable data used with 2 nuclides:

   94239.03c (from 2.50E-03 to 3.00E-02 MeV)
   94240.03c (from 5.70E-03 to 4.00E-02 MeV)

 - Sampling used from 2.50E-03 to 4.00E-02 MeV

OK.

Sorting material-wise reaction lists:

   0% complete
 100% complete

Calculating macroscopic cross sections:

   0% complete
  67% complete
 100% complete

Calculating DT neutron majorant cross section:

   0% complete
 100% complete

Clearing results and statistics...
OK.

Sampling initial source...
OK.


***** Wed May 26 16:34:40 2021:

 - MPI task         = 0
 - OpenMP thread    = 16
 - RNG parent seed  = 1622043278
 - RNG history seed = 3213952626747992718
 - RNG history idx  = 99995

Fatal error in function StopAtBoundary:

Crossed boundary not within line-of-sight

Simulation aborted.


***** Wed May 26 16:34:40 2021:

 - MPI task         = 0
 - OpenMP thread    = 15
 - RNG parent seed  = 1622043278
 - RNG history seed = 7989030176455551630
 - RNG history idx  = 99996

Fatal error in function 996

Fatal error in function StopAtBoundary:

Crossed boundary not within line-of-sight
Does anyone know what I should do? Any help would be greatly appreciated.
Thanks!

Ana Jambrina
Posts: 550
Joined: Tue May 26, 2020 5:32 pm
Security question 1: No
Security question 2: 7

Re: Fatal error in function StopAtBoundary and in function 996

Post by Ana Jambrina » Wed May 26, 2021 8:35 pm

The problem arises from the initial source definition for the given geometry and the axial vacuum boundary condition.
- Ana

jdaniels
Posts: 2
Joined: Wed May 26, 2021 6:55 pm
Security question 1: No
Security question 2: 7

Re: Fatal error in function StopAtBoundary and in function 996

Post by jdaniels » Wed May 26, 2021 10:50 pm

Hi Ana,

Thanks for replying so promptly - moving the source points into the cells has fixed the issue :)

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