5.6 KiB
If automatic time incrementation is not selected in the analysis procedure, values of PNEWDT that are greater than 1.0 will be ignored and values of PNEWDT that are less than 1.0 will cause the job to terminate.
ENER
Energy per unit mass stored in the fluid. This variable is used for energy output only and has no effect on the solution.
Variables passed in for information
PRESS
Fluid cavity pressure at the end of the increment. For a linear perturbation step this is the base state pressure.
DPRESS
Fluid cavity pressure increment. For a linear perturbation step this value is zero.
PRESSI
Fluid cavity pressure at the beginning of the analysis.
TEMP
Fluid cavity temperature at the end of the increment. For a linear perturbation step this is the base state temperature.
DTEMP
Fluid cavity temperature increment. For a linear perturbation step this value is zero.
TEMPI
Fluid cavity temperature at the beginning of the analysis.
TIME(1)
Current value of step time at the start of the increment.
TIME(2)
Current value of total time at the start of the increment.
DTIME
Time increment.
KSTEP
Step number.
KINC
Increment number.
NONUM
Cavity reference node number.
FLNAME
User-specified fluid property name, left justified.
LFLAG
Linear perturbation flag for the step. If this is a linear perturbation step, LFLAG=1. For a general analysis step LFLAG=0.
1.1.34 UFLUIDCONNECTORLOSS: User subroutine to define the loss coefficient for fluid flow in fluid pipe connector elements.
Product: Abaqus/Standard
Reference
• *FLUID PIPE CONNECTOR LOSS
Overview
User subroutine UFLUIDCONNECTORLOSS:
• can be used to define the loss coefficient in a fluid pipe connector element;
• corresponds to the Darcy-Weisbach equation for pressure loss; and
• can be used with the fluid pipe connector elements.
User subroutine interface
subroutine ufluidconnectorloss (
C Write only -
* ak1, ak2,
C Read only -
* coords, flow, rho, visc,
* dia, area,
* ndim, jelno, kStep, kInc,
* time,
* nIarray,
* i_array,
* nRarray,
* r_array,
* ncarray,
* c_array)
C
include 'aba_param.inc'
C
dimension time(2),
* coords(2*ndim),
* i_array(nIarray),
* r_array(nRarray)
C
character*80 c_array(ncarray)
C
user coding to define connector friction values
return
end
Variables to be defined
ak1
This connector loss coefficient must be updated and is used when the flow is from node 1 to node 2.
ak2
This connector loss coefficient must be updated and is used when the flow is from node 2 to node 1.
Variables passed in for information
coords(2*ndim)
Array containing original coordinates of the element. coords(1:ndim) is the coordinate of the first node, and coords(ndim+1:2*ndim) is the coordinate of the second node.
flow
Current flow rate through the element.
rho
Current density of fluid flowing through the pipe.
visc
Current viscosity of fluid flowing through the pipe.
dia
User-specified hydraulic diameter.
area
User-specified hydraulic area.
ndim
Dimension of the element.
jelno
User element number for which friction coefficient is required.
kStep
Step number.
kInc
Increment number.
time(1)
Current step time.
time(2)
Total time.
nIarray
Size of array i_array.
i_array
Integer array for future expansion.
nRarray
Size of array r_array.
r_array
Real array for future expansion.
ncarray
Size of array c_array.
c_array
Character array for future expansion.
1.1.35 UFLUIDCONNECTORVALVE: User subroutine to define the valve opening to control flow in fluid pipe connector elements.
Product: Abaqus/Standard
Reference
• *FLUID PIPE CONNECTOR LOSS
Overview
User subroutine UFLUIDCONNECTORVALVE:
• can be used to control the valve opening to turn off or turn on fluid flow; and
• can be used with fluid pipe connector elements.
User subroutine interface
subroutine ufluidconnectorvalve (
C Write only -
* valveOpening,
C Read only -
* coords, flow, rho, visc,
* dia, area,
* ndim, jelno, kStep, kInc,
* time,
* nIarray,
* i_array,
* nRarray,
* r_array,
* ncarray,
* c_array)
C
include 'aba_param.inc'
C
dimension time(2),
* coords(2*ndim),
* i_array(nIarray),
* r_array(nRarray)
C
character*80 c_array(ncarray)
C
user coding to define control valve opening
return
end
Variable to be defined
valveOpening
The value of this variable must be set between 0.0 (closed/shut-off) and 1.0 (fully open) to determine whether the valve is fully or partially open or closed.
Variables passed in for information
coords(2*ndim)
Array containing the original coordinates of the element. acoords(1:ndim) is the coordinate of the first node, and acoords(ndim+1:2*ndim) is the coordinate of the second node.
flow
Current flow rate through the element.
rho
Current density of fluid flowing through the pipe.
visc
Current viscosity of fluid flowing through the pipe.
dia
User-specified hydraulic diameter.
area
User-specified hydraulic area.
ndim
Dimension of the element.
jelno
User element number for which a friction coefficient is required.
kStep
Step number.
kInc
Increment number.
time(1)
Current step time.
time(2)
Total time.
nIarray
Size of array i_array.
i_array
Integer array for future expansion.
nRarray
Size of array r_array.
r_array
Real array for future expansion.
ncarray
Size of array c_array.
c_array
Character array for future expansion.