*HEADING
 : F2D2 FLUID ELEMENT AND FLUID LINK TEST 
 (2-1x1x1 BLOCKS, HYDRAULIC, NO BULK MODULUS, NO THERMAL EXPANSION)
*RESTART, WRITE, FREQ=1
*NODE, NSET=CAV1NOD
  1, 1., 1.
  2, 2., 1.
  3, 2., 2.
  4, 1., 2.
  5, 3., 1.
  6, 3., 3.
  7, 1., 3.
*NODE, NSET=CAV2NOD
 11, 4., 1.
 12, 5., 1.
 13, 5., 2.
 14, 4., 2.
 15, 6., 1.
 16, 6., 3.
 17, 4., 3.
*ELEMENT, TYPE=CPE4, ELSET=STRUCTURE
  1,  2,  5,  6,  3
  2,  3,  6,  7,  4 
 11, 12, 15, 16, 13
 12, 13, 16, 17, 14 
*SOLID SECTION, ELSET=STRUCTURE, MATERIAL=ELAS
*MATERIAL, NAME=ELAS
*ELASTIC
 1.0E6
*SURFACE,TYPE=ELEMENT,NAME=CAV1
 1, S4
 2, S4
*SURFACE,TYPE=ELEMENT,NAME=CAV2
 11, S4
 12, S4
*PHYSICAL CONSTANTS, ABSOLUTE ZERO = 0
*FLUID CAVITY, NAME=CAVITY1, BEHAVIOR=FLUID, SURFACE=CAV1, REFNODE=1
 1.0
*FLUID CAVITY, NAME=CAVITY2, BEHAVIOR=FLUID, SURFACE=CAV2, REFNODE=11
 1.0
*FLUID BEHAVIOR, NAME=FLUID
*FLUID DENSITY
10., 
**
*FLUID EXCHANGE, NAME=LINK, PROP=LINKBEHAVIOR
 1,11
*FLUID EXCHANGE PROPERTY, NAME=LINKBEHAVIOR, DEPEND=1, TYPE=BULK VISCOSITY
 10.0, 0.0,   ,  10.0, 1.0
  1.0, 0.0,   , 100.0, 1.0
 10.0, 0.001, ,  10.0, 2.0
  1.0, 0.001, , 100.0, 2.0
**
**              SPRINGS
**
*ELEMENT, TYPE=SPRING1, ELSET=SPRINGY1
 21, 4
 41, 14
*SPRING, ELSET=SPRINGY1
 2, 
 1.E-6,
*BOUNDARY
  2, 1, 2, 0.0
  4, 1, 1, 0.0
 12, 1, 2, 0.0
 14, 1, 1, 0.0
*INITIAL CONDITIONS, TYPE=TEMPERATURE
  1, 10.
 11, 10.
*INITIAL CONDITIONS, TYPE=FIELD, VARIABLE=1
  1, 1.0
 11, 1.0
*EQUATION
  2, 
  3, 1, 1.0,  2, 1, -1.0
  2, 
  3, 2, 1.0,  4, 2, -1.0
  2, 
 13, 1, 1.0, 12, 1, -1.0
  2, 
 13, 2, 1.0, 14, 2, -1.0
*NSET,NSET=REFNODE
 1,11
**
**              STEP 1: CONCENTRATED LOAD OF -100
**                      FIELD VARIABLE = 1
**                      TEMPERATURE    = 10
**
*STEP, NLGEOM, AMPLITUDE=STEP
*STATIC
 0.1, 0.2
*MODEL CHANGE, REMOVE
 STRUCTURE
*CLOAD
 4, 2, -100.
*NODE PRINT
 U,PCAV,CVOL
*OUTPUT,FIELD
*NODE OUTPUT
 U,
*OUTPUT,HISTORY
*NODE OUTPUT, NSET=REFNODE
PCAV,CVOL
*EL PRINT
 MFL,MFLT
*OUTPUT,FIELD
*ELEMENT OUTPUT
 MFL,MFLT
*ENERGY PRINT
*OUTPUT,HISTORY,FREQUENCY=1
*ENERGY OUTPUT,VARIABLE=PRESELECT
*END STEP
**
**              STEP 2  FIELD VARIABLE = 1
**                      TEMPERATURE    = 10 TO 100
**
*STEP, NLGEOM
*STATIC
 0.005, 0.01
*TEMPERATURE
  1, 100.
 11, 100.
*END STEP
**
**              STEP 3  DUMMY PERTURBATION
**                      FIELD VARIABLE = 1
**                      DELTA TEMPERATURE  = 0
**
*STEP,PERTURBATION
*STATIC
 0.005, 0.01
*NODE PRINT
 NT, 
*OUTPUT,FIELD
*NODE OUTPUT
 NT,
*ENERGY PRINT
*OUTPUT,HISTORY,FREQUENCY=1
*ENERGY OUTPUT,VARIABLE=PRESELECT
*END STEP
**
**              STEP 4  FIELD VARIABLE = 2
**                      TEMPERATURE    = 100
**
*STEP, NLGEOM, AMPLITUDE=STEP
*STATIC
 0.01, 0.01
*FIELD, VARIABLE=1
  1, 2.0
 11, 2.0
*END STEP