Hello.
Can anyone help me with my problem, please? I am working on my project and the task is modal analysis of tank on elastic foundation in Ansys APDL. Elastic foundation is represented by Winkler's model.
For elastic stiffness foundation I used element type SURF154 and add real constant.
This element I surfed to the bottom of the tank. Then I set boundary condition to the base of the tank - fixed displacement to all base without displacement in direction UZ.
Eigenfrequencies of this tank are much lower (1st freq. = 11 Hz) than the tank resting on the rigid foundation (1st freq.=120 Hz). I think that is not correct because I think that eigenfrequencies of the tank on elastic foundation should be higher than tanks on rigid foudnation. I think that I set wrong boundary conditions which should represent Winkler's model.
Could anyone help me?
Thanks.
Can anyone help me with my problem, please? I am working on my project and the task is modal analysis of tank on elastic foundation in Ansys APDL. Elastic foundation is represented by Winkler's model.
For elastic stiffness foundation I used element type SURF154 and add real constant.
This element I surfed to the bottom of the tank. Then I set boundary condition to the base of the tank - fixed displacement to all base without displacement in direction UZ.
Eigenfrequencies of this tank are much lower (1st freq. = 11 Hz) than the tank resting on the rigid foundation (1st freq.=120 Hz). I think that is not correct because I think that eigenfrequencies of the tank on elastic foundation should be higher than tanks on rigid foudnation. I think that I set wrong boundary conditions which should represent Winkler's model.
Could anyone help me?
Thanks.
