How does a fluid behave inside of a spherical cavity?

[Domenico94]

Suppose you have a spherical cavity, with a flow of a fluid ( in particular water), entering it from one side. What will happen to this flow? Will it create turbulences? Will speed increase? Will eventual waves entering the cavity be reflected, so creating waves with bigger amplitude?
Suppose the cavity is closed and doesn't allow water to exit .Only to enter.

 

[BvU]

What's inside the cavity ? If there's air it will be compressed while th cavern fills up. You'll have to tell us some more details for this scenario to work it out ...

 

[Domenico94]

Suppose it is on the surface of the sea, for example. So, the lower part is filled with water. The upper part is filled with air.

 

[BvU]

Why do you bring in the sea ? Try to paint a complete picture and set up a complete problem description. We're not telepathic.
Ideal fluid ? 'Infinite pressure' allowed ? What causes the influx ?