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[Sergiomedina_sm]

I  am Sergio a student at the Polytechnic University of Castilla La Mancha (Ciudad Real). I am doing my end of studies work on the structural calculation of a water tank.

I am working with a SHELL63 tank for the tank walls; and a FLUID30 element, for the volume of water.

I am doing dynamic simulations: modal analysis and spectral analysis.

However, when I look at the displacement or warp of the modes, I only get the deformation of the fluid volume. I did not observe the deformation of the tank due to the fluid-structure interactions. How can I observe this? I am sending you my code so you can tell me how you can resolve this question; and if it has any bugs or improvements:

/PREP7

CSYS,1

*AFUN,DEG

/VUP,,Z

! ---------- CONSTANTS OR VARIABLES ----------

G = 9.81! Gravity acceleration

H1 = 1! LIQUID HEIGHT

H2 = 6! Total height of the tank

DIAM = 8! Fluid diameter

RAD = DIAM / 2! Fluid radius

PS = 7850! Steel mass density

IS = 206e9! Modulus of elasticity of steel in Pa (N / m2)

PW = 1000! Mass density of water

CW = 1483! SOUND SPEED WATER M / S

TAMEL = 0.3! TANK ELEMENT SIZE

ESP = 0.005! THICKNESS

MODES = 600! NUMBERS OF MODES

! -------- MATERIAL PROPERTIES --------

!

ET, 1, FLUID30! FLUID

MP, SONC, 1, CW

MP, DENS, 1, PW

R, 1

!

ET, 2, SHELL63! DEPOSIT

MP, EX, 2, ES

MP, PRXY, 2,0.3

MP, DENS, 2, PS

R, 2, ESP

!

! --------- FLUID DESIGN ------

!

CYL4,0,0, RAD, 45

AGE, 4,1 ,,,, 45

AGLUE, ALL

NUMMRG, KP

NUMCMO, ALL

ALLSEL

VEXT, ALL ,,,,, - H1

VGLUE, ALL

NUMMRG, KP

NUMCMO, ALL

ALLSEL

!

! ------- TANK WALL DESIGN -------

!

K, 13, RAD, 0, H2-H1

K, 14, RAD, 45, H2-H1

K, 15, RAD, 90, H2-H1

K, 16, RAD, 135, H2-H1

K, 17, RAD, 180, H2-H1

A, 1, 2, 14, 13

A, 2,4,15,14

A, 4,5,16,15

A, 5,6,17,16

ASEL, S ,,, 18,21,1

AGLUE, ALL

NUMMRG, KP

NUMCMO, ALL

ALLSEL

!

! ------ MESHING OF THE FLUID -----

!

TYPE 1

MAT, 1

R, 1

MSHAPE, 0.3D

MSHKEY, 1

AESIZE, EVERYONE, TAMEL

VMESH, ALL

NSEL, S ,,, ALL

CM, FLUID, NODE

ALLSEL

!

! ---------- MALLED DEPOSIT --------

!

TYPE 2

MAT, 2

REAL, 2

MSHAPE, 0.3D

MSHKEY, 1

ASEL, S ,,, 18,21,1

ASEL, A ,,, 10,16,3

ASEL, A ,,, 6

AESIZE, EVERYONE, TAMEL

AMESH, ALL

ALLSEL

!

! ---------- CONDITIONS OF CONDITIONS ----------

!

NSEL, S, LOC, Z, -H1! SOIL NODES IMPEDED UX, UY, UZ

D, ALL, UX

D, EVERYONE, OU

D, EVERYONE, UZ

ALLSEL

NSEL, S, LOC, Z, 0! FREE CC WATER SHEET

SF, ALL, FREE

ALLSEL

CMSEL, S, FLUID! LIQUID WALLS CC FSI

NSEL, R, LOC, X, RAD

ESLN, S

ESEL, R, TYPE ,, 1

SF, ALL, FSI

ALLSEL

CSYS, 0

NSEL, S, LOC, Y, 0! PLANE NODES Y = 0 I PREVENT UY

D, ALL, UY

ALLSEL

ESEL, R, TYPE ,, 2! NODES MAT 2 IMPIDO ROTZ

NSLE

NSEL, R, LOC, Y, 0

D, ALL, ROTZ

CSYS, 1

ALLSEL

!

! --------- MODAL ANALYSIS ----------

!

/ SOLU

ANTYPE, MODAL

ACCEL, 0.0, G

MODOPT, UNSYM, MODES!, 50,1000

MXPAND, MODES ,,, YES

/ OUTPUT, DEP_LIQ3D, TXT

SOLVE

/ OUTPUT

SAVE

FINISH

!

! ---------- SPECTRAL ANALYSIS ----------

!

/ SOLU

ANTYPE, SPECTRUM

SPOPT, SPRS

SVTYP, 2.1

FREQ, 1e-2, .25,1,5,10,15,20,25,30

SV, 0,1,1,1,1,1,1,1,1,1

SED, 1.0,0.0,0.0

SRSS

/ OUTPUT, DEP_LIQ3D, TXT ,, APPEND

SOLVE

/ OUTPUT

SAVE

FINISH

!

/ POST1

RSYS, SOLU

/ INPUT, DEPOSCIL3D, MCOM

SAVE

[mrife]

Hi Sergiomedina_sm Please check the commands against the MAPDL Command Guide in the Help. AGE is not a APDL command and will do nothing...I suspect you mean to use AGEN? NUMCMO is not a APDL command...guess a simple typo and you mean to use NUMCMP. The Component 'EVERYONE' is not defined but used four times. And all the fluid elements have structural degrees-of-freedom. Usually we define two element types; fluid30 with and fluid30 without structural DOFs and set just those fluid elements connected to structural elements with the [fluid] type that has structural dof.
The entity numbering does not seem to be what you expect - perhaps due to the NUMCMP command not being used - so some of the other operations like meshing fail. Once you've edited the input file run it and see if there are any remaining warnings/errors about failed geometry operations and/or meshing.
Mike

[Sergiomedina_sm]

Hello, if you excuse me I must have sent the code wrong. I send you the correct code.

Also, I have not understood what you mean in the second part of your answer: ¨And all the fluid elements have structural degrees-of-freedom. Usually we define two element types; fluid30 with and fluid30 without structural DOFs and set just those fluid elements connected to structural elements with the [fluid] type that has structural dof.¨

MODES = 600 ! NUMBERS OF MODES

-------- MATERIAL PROPERTIES --------
ET, 1, FLUID30 ! FLUID
MP, SONC, 1, CW
MP, DENS, 1, PW
R, 1
!
ET, 2, SHELL63 ! DEPOSIT
MP, EX, 2, ES
MP, PRXY, 2,0.3
MP, DENS, 2, PS
R, 2, ESP
!

! --------- FLUID DESIGN ------
!
CYL4,0,0, RAD, 45
AGEN, 4,1 ,,,, 45
AGLUE, ALL
NUMMRG, KP
NUMCMP, ALL
ALLSEL
VEXT, ALL ,,,,, - H1
VGLUE, ALL
NUMMRG, KP
NUMCMP, ALL
ALLSEL

! ------- TANK WALL DESIGN -------
!
K, 13, RAD, 0, H2-H1
K, 14, RAD, 45, H2-H1
K, 15, RAD, 90, H2-H1
K, 16, RAD, 135, H2-H1
K, 17, RAD, 180, H2-H1
A, 1, 2, 14, 13
A, 2,4,15,14
A, 4,5,16,15
A, 5,6,17,16
ASEL, S ,,, 18,21,1
AGLUE, ALL
NUMMRG, KP
NUMCMP, ALL
ALLSEL
!
! ------ MESHING OF THE FLUID -----
!
TYPE 1
MAT, 1
R, 1
MSHAPE, 0.3D
MSHKEY, 1
AESIZE,ALL,0.3
VMESH, ALL
NSEL, S ,,, ALL
CM, FLUID, NODE
ALLSEL
!
! ---------- MALLED DEPOSIT --------
!
TYPE 2
MAT, 2
REAL, 2
MSHAPE, 0.3D
MSHKEY, 1
ASEL, S ,,, 18,21,1
ASEL, A ,,, 10,16,3
ASEL, A ,,, 6
AESIZE, ALL,0.3
AMESH, ALL
ALLSEL
!
! ---------- CONDITIONS OF CONDITIONS ----------
!
NSEL, S, LOC, Z, -H1 ! SOIL NODES IMPEDED UX, UY, UZ
D, ALL, UX
D, ALL,UY
D,ALL, UZ
ALLSEL
NSEL, S, LOC, Z, 0 ! FREE CC WATER SHEET
SF, ALL, FREE
ALLSEL
CMSEL, S, FLUID ! LIQUID WALLS CC FSI
NSEL, R, LOC, X, RAD
ESLN, S
ESEL, R, TYPE ,, 1
SF, ALL, FSI
ALLSEL
CSYS, 0
NSEL, S, LOC, Y, 0 ! PLANE NODES Y = 0 I PREVENT UY
D, ALL, UY
ALLSEL
ESEL, R, TYPE ,, 2 ! NODES MAT 2 IMPIDO ROTZ
NSLE
NSEL, R, LOC, Y, 0
D, ALL, ROTZ
CSYS, 1
ALLSEL
!
! --------- MODAL ANALYSIS ----------
!
/ SOLU
ANTYPE, MODAL
ACEL, 0,0, 9.81
MODOPT, UNSYM, MODES !, 50,1000
MXPAND, MODES ,,, YES
/ OUTPUT, DEP_LIQ3D, TXT
SOLVE
/ OUTPUT
SAVE
FINISH

!
! ---------- SPECTRAL ANALYSIS ----------
!
/ SOLU
ANTYPE, SPECTRUM
SPOPT, SPRS
SVTYP, 2.1
FREQ, 1e-2, .25,1,5,10,15,20,25,30
SV, 0,1,1,1,1,1,1,1,1,1
SED, 1.0,0.0,0.0
SRSS
/ OUTPUT, DEP_LIQ3D, TXT ,, APPEND
SOLVE
/ OUTPUT
SAVE
FINISH
!
/ POST1
RSYS, SOLU
/ INPUT, DEPOSCIL3D, MCOM
SAVE

[Sergiomedina_sm]

I still can't figure this out. I need help!

[Ashish Khemka]

I will close this post as you have one more similar post:

Tank axilsymmetric symmetry in ANSYS MECHANICAL APDL. ÔÇö Ansys Learning Forum

Regards Ashish Khemka