## General Mechanical

#### How to model 2way FSI in a rotating tank?

• masoudmtl
Subscriber

Hello everybody,

I have been busy with this problem for over a month and I would

really appreciate it if someone could give me a kind help or introduce me to a

helpful reference. Here is the problem:

There is a tank that is half full with water and half with air.

There are a number of springs inside the tank which would vibrate with the

rotation of the tank and interact with the water and create some moments on the

structure of the cylinder. In detail:

1.      Consider a circular tank

with a diameter of 20cm and a height of 20 cm. The wall of the tank is 5mm

thick.0

2.       There exist 4

springs attached to the floor of the tank in a circular pattern. Each spring is

attached like a cantilever beam. That is one end attached to the floor of the

tank and the other end is free.

3.      Also consider that the

axis of the springs is parallel to the axis of the cylinder but 5cm apart

radially. Each spring has a wire thickness of 0.2mm and is 20 cm tall with 50

turns.

4.      The water height is 10cm

inside the tank and the rest is air. Also, gravity acts downward in the

direction of the axis of the cylinder.

5.      Imagine the tank is

rotated with a varying rotational velocity of 100*sin(2*3.14*t) around its

axis.

It is desired to measure the torque on the tank with time. We are

going to drive the system with a motor and we are interested to have an

estimate of the behavior of the system. Clearly, the problem is a 2way FSI

(Fluid-Structure interaction). My problem in the first place is in coupling the

Ansys transient structural with Ansys Fluent. In detail, I want the Ansys

Fluent module to recognize the rotation from the structural module and apply it

to the fluid. Then, I am interested to see the interaction between vibrating

springs and the water inside the tank.

I am enthusiastically waiting for your responses my friends.

Thanks,

Masoud

• 1shan
Ansys Employee