Task SetSrc

The task SetSrc generates emission source terms for the different species. It can also perform a-priori particle aggregation and apply a TGSD cut-off.

Input files

This task requires the namelist file name.inp and the files:

  • name.tgsd.species generated by the task SetTGSD with the Total Grain Size Distributions (TGSD) for each species
  • name.dbs.pro profile file generated by the task SetDbs

Output files

The granulometry file

The granulometry file name.grn is an ASCII file containing information about each bins, including aggregates (if any) and definition of effective bins. This file is created by the SetSrc task from the preliminary TGSD file(s) (i.e., name.tgsd.species). The file format is described in the Table below:

Column 1Column 2Column 3Column 4Column 5Column 6Column 7Column 8Column 9

where the symbols mean:

nctotal number of bins
nc_effnumber of effective bins
diambin diameter in \(mm\)
rhobin density in \(kg~m^{-3}\)
sphebin sphericity
fcbin mass fraction satisfying \(\sum fc = 1\)
cat_codebin category code (see Table below)
spe_codebin species code (see Table below)
spe_namebin species name (see Table below)
spe_tagbin tag name (for descriptive purposes only)
activelogical value specifying if the bin is effective or not.

The table below specifies the codes assigned to different species:

category typecategory codespecies codespecies name

Example with 7 classes without cut-off:

   7     7
  4.000000   1200.0   0.900  0.137572886E+00   1   1      tephra      lapilli-01  T
  1.000000   1357.1   0.900  0.924286798E-01   1   1      tephra   coarse_ash-01  T
  0.250000   1671.4   0.900  0.194773804E+00   1   1      tephra   coarse_ash-02  T
  0.062500   1985.7   0.900  0.384212886E+00   1   1      tephra     fine_ash-01  T
  0.015625   2300.0   0.900  0.175148480E+00   1   1      tephra     fine_ash-02  T
  0.003906   2300.0   0.900  0.158632644E-01   1   1      tephra     fine_ash-03  T
  0.001000   1000.0   1.000  0.100000000E-01   2   4         SO2             SO2  T

The source file

The source file name.src is an ASCII file containing the definition of the source term. The source can be defined for different time phases during which source values are kept constant. The number, position and values (i.e., Mass Flow Rate) of the source points can vary from one time slice to another and cannot overlap. There is no restriction on the number and duration of the time slices. It allows, in practice, to discretize any kind of source term. This file can be defined directly by the user or generated by the SetSrc task. The format of the file is described in the next table (nc=6 is assumed in the example):

Column 1Column 2Column 3Column 4Column 5Column 6

This block is repeated for each eruption phase.

The symbols mean:

time1Source phase starting time in seconds after 00:00 UTC of the run day
time2Source phase end time in seconds after 00:00 UTC of the run day
nsrcNumber of source points for this phase. It can vary from one phase to another
ncTotal number of (effective) bins
MFRMass Flow Rate in \(kg~s^{-1}\)
x(i)Longitude of the source i
y(i)Latitude of the source i
z(i)Height in meters a.g.l. of the source i
src(i,j)Mass flow rate in \(kg~s^{-1}\) of bin j and the source point i

The mass flow rate must verify \(\sum \sum src(i,j) = MFR\).

Example for an emission column with 4 particle classes corresponding to a 1-h phase:

  75600   79200
    100       4
  -72.112200  -40.582800      1520.   0.977000246E+02  0.326596193E+02  0.171776303E+02  0.740473318E+01
  -72.112200  -40.582800      1620.   0.113424788E+03  0.379161663E+02  0.199423601E+02  0.859652075E+01
  -72.112200  -40.582800     11320.   0.334110824E+01  0.111688122E+01  0.587434061E+00  0.253224246E+00
  -72.112200  -40.582800     11420.   0.000000000E+00  0.000000000E+00  0.000000000E+00  0.000000000E+00