> stuffing a bunch of small straws in the main tube helps, because if you have a lot of smaller tubes - (especially with water) you can get the effective "orientation of the molocules" the same - so your stream can be more cohesive
This is not the right way to think about it. The straws reduce turbulence by preventing fluid motion in a radial direction, and reduce swirl by preventing a swirling motion. (The screens have similar effects.) Both turbulence and swirl prevent the formation of a coherent liquid jet. The straws (and screens) aren't without disadvantages as they will cause significant pressure losses.
How I know: I did a PhD on the range of large fire-fighting water jets and ended up reading a LOT of laminar fountain stuff online out of curiosity.
> this method was (invented?employed) by Disney Land Engineers when they were building the fountains that shoot clean, cohesive lasers of water
Definitely employed. Flow straighteners (or flow conditioners, or whatever you want to call them) were quite common for turbulence and swirl reduction in general before laminar fountains appeared. I recall seeing patents with flow straighteners for fire-fighting purposes in the 1930s, and I'm confident that they were in use in other areas earlier than that.
***
A side note: Laminar fountains are neat, but you'll find a ton of misinformation about how they work online. I started writing more, but Brandolini's law comes into play, and I don't have the time to go into it.
This is not the right way to think about it. The straws reduce turbulence by preventing fluid motion in a radial direction, and reduce swirl by preventing a swirling motion. (The screens have similar effects.) Both turbulence and swirl prevent the formation of a coherent liquid jet. The straws (and screens) aren't without disadvantages as they will cause significant pressure losses.
How I know: I did a PhD on the range of large fire-fighting water jets and ended up reading a LOT of laminar fountain stuff online out of curiosity.
> this method was (invented?employed) by Disney Land Engineers when they were building the fountains that shoot clean, cohesive lasers of water
Definitely employed. Flow straighteners (or flow conditioners, or whatever you want to call them) were quite common for turbulence and swirl reduction in general before laminar fountains appeared. I recall seeing patents with flow straighteners for fire-fighting purposes in the 1930s, and I'm confident that they were in use in other areas earlier than that.
***
A side note: Laminar fountains are neat, but you'll find a ton of misinformation about how they work online. I started writing more, but Brandolini's law comes into play, and I don't have the time to go into it.