Real-life phenomenon/application of this fluid dynamics model

[rakso]

Hi!

Water is flowing in a converging duct, with the angle α, see the figure.

My task is to find a real-life phenomenon / application of this model, and later solve it numerically / analytically where this fluidproblem occurs. However, my imagination is kinda slow today, what are some fun / trivial / hard applications this? I'm just looking for some different applications to wrap my head around this. Thanks!

 

[Baluncore]

Decorating a cake. Conical pastry bag, with conical decorating tips.
https://www.recipetips.com/kitchen-tips/t--1640/cake-decorating-supplies.asp

 

[rakso]

Decorating a cake. Conical pastry bag, with conical decorating tips.
https://www.recipetips.com/kitchen-tips/t--1640/cake-decorating-supplies.asp

I like this suggestion! I suppose it's not water that flows though, but perhaps the fluid has the same properties?

 

[Baluncore]

A conical funnel is used in the kitchen to fill a bottle.

 

[rakso]

A conical funnel is used in the kitchen to fill a bottle.

True. However, doesn't the problem become spherical?

 

[Baluncore]

However, doesn't the problem become spherical?

Yes.
But where does anyone need a sheet of high speed water, that is possibly still converging?
A 1D convergence might imply a rectangular supply pipe.
When do you need to "paint" an area efficiently?

 

[Chestermiller]

The "curtain coating" coating process involves converging flow like this, followed by a vertical drop to a moving web.
https://en.wikipedia.org/wiki/Curtain_coating