1. Main riser line specification

1.1. Data group identifier, one input line

The main riser line (MRL) may be used to define continuous contents of several lines.

This data group may be given for AR-systems only. Only one riser system may be defined on the INPMOD input file.

MAIN RISEr LINE
Main riser line definition, one input line
MRL-ID LINE-ID1 ... LINE-IDn

  • MRL-ID: character(8): Main riser line identifier

  • LINE-ID1: character(8): Reference to line identifier

    • LINE-ID1 = First line in MRL

    • By default the MRL is defined from end 1 to end 2 of this line

    • If the line ID is given subsequent to a minus sign, -LINE-ID1, the MRL is defined from end 2 to end 1 of this line

  • …

  • LINE-IDn: integer:

A MRL may consist of up to 200 lines. A maximum of 5 MRLs may be defined.

Main riser line flow, one input line
RHOI IEND PRESSI DPRESS VVELI

  • RHOI: real, default: 0: Density of contents \(\mathrm {[M/L^3]}\)

  • IEND: integer:

    • IEND=1: Pressure specified at end 1

    • IEND=2: Pressure specified at end 2

  • PRESSI: real, default: 0: Pressure at end IEND \(\mathrm {[F/L^2]}\)

  • DPRESS: real, default: 0: Pressure drop \(\mathrm {[F/L^3]}\)

  • VVELI: real, default: 0: Fluid velocity \(\mathrm {[L^3/T]}\)

    • Dummy in present version

The pressure drop is assumed to be uniform over the line length starting at end IEND. The values given here will replace values given in the FLUID specification.

An illustration is shown the figure `Main riser line concept' below with corresponding input data.

um MRL definition
Figure 1. Main riser line concept

Input using the main riser line concept is shown below.

'**********************************************************************
 ARBITRARY SYSTEM AR
'**********************************************************************
'nsnod nlin nsnfix nves nricon nspr nakc
 3     2    3      0    0      0    0
'ibtang zbot             ibot3d
 0      -1.000000000e+03 0
'B 6.5: LINE TOPOLOGY DEFINITION
'lineid lintyp-id snod1-id snod2-id
 line1  ltyp1     node1    node2
 line2  ltyp1     node3    node2
'FIXED NODES
'
..
.
...
.
'**********************************************************************
 MAIN RISER LINE
'**********************************************************************
'IMRL LINE-ID(i)
 MRL1 line1 -line2
'rhoi            iend pressi          dpress
 5.000000000e-01 1    1.000000000e+03 0.000000000e+00
'**********************************************************************
 NEW COMPONENT CRS0
'**********************************************************************
.
..
...