Transient internal pressure

[Eleo]

I want to define a transient internal pressure in a pipeline using an input file and the subroutine DLOAD

1) I use as a starting point the input file at constant pressure:
I use the file.inp as an input file. The loads are defined as:
** LOADS
**
** Name: Load-1 Type: Pressure
*Dsload
Surf-1, P, 7000.
**

2) For the transient internal pressure, I modify the load part in the input file at constant pressure (1) and use a dload subroutine:
** LOADS
**
** Name: Load-1 Type: Pressure
*Dload
Surf-1
**

When I launch the file with Constant pressure (1), it is working ok.
When I launch the transient internal pressure input file (2) and the dload subroutine, I have the following error:
***ERROR: in keyword *DLOAD, file “Job-1.inp”, line 22935: Unknown assembly
element set SURF-1

Why do I have this error?

 

[Mustaine3]

Try *Dsload in file (2).

 

[Eleo]

To test the dload subroutine, I modelled the pressure by two ways
1) Using the input file with the loads written as:

** LOADS
**
** Name: Load-1 Type: Pressure
*Dsload
Surf-1, P, 7000.
**

2) Using the input file with loads written as below and also using a dload subroutine:
** LOADS
**
** Name: Load-1 Type: Pressure
*Dsload
Surf-1,P
**

SUBROUTINE DLOAD(F, KSTEP, KINC, TIME, NOEL, NPT,&
& LAYER, KSPT, COORDS, JLTYP, SNAME)
INCLUDE 'ABA_PARAM.INC'
DIMENSION COORDS(3),TIME(2)
CHARACTER*80 SNAME
DATA P0/7000./
F=P0
RETURN
END

Why these two options does not give the same result?

 

[Mustaine3]

I've tried a simple example and it's working fine.

Try
*Dsload
Surf-1, PNU, 1


And to ramp up the user load like a regular load, you might use
F=P0*TIME(1)