Printing a model jet engine is quite an accomplishment. But it wasn’t enough for [linus3d]. He wanted to redesign it to have a turbojet, an afterburner, and a variable exhaust nozzle. You can see how it all goes together in the video below.
This took months of work and it shows. This probably won’t make a good rainy-day weekend project. You do need a few ball bearings and some M2 hardware, but it is mostly 3D printed.
True turbojets are most often found on military planes. They are loud, don’t perform well at low speeds, and are generally not very efficient. A variation, the turbofan, is what you usually find on passenger jets. They are quieter and work better at low speeds, but have more parts and, thus, more maintenance.
Unlike a true turbojet, turbofan engines have a cold section and a hot section. The bypass ratio refers to how much air flows through the cold path relative to the amount flowing through the hot path. This cold air provides additional thrust, making the turbofan engine more efficient, especially at lower speeds. The reduced demand on the hot air thrust also reduces the amount of noise.
Plastic isn’t going to cut it for a real jet engine, although you can 3D print some parts of one. Bonus hacker cred if you build your jet engine by hand.
Protip: skip to 4:35, all the important content starts from there.
That engine does not go turbo, it just sits there. Beautiful model work but what a click-bait title. Al, you can do better.
+1 …. Agreed ….. title is click bait and should have the word ‘model’ in it.
Real jet components can be printed with incanel.
If you printed this in metal, all you’d have is a metal model.
Looks like a cheap toy that would be a lot cheaper to make with injection molding.
On what planet?
As always.
One is much cheaper to print.
But if you need 1000?
Still cheaper to print.
Molds are expensive and you’d need many to make this model.
Pure turbojets also have a cold and hot section. The cold section just refers to the compressor section of the engine, and the hot section is the power turbine. Turbofans have initial compressor section that includes the fan, and from that the bypass ratio is determined by what is directed into the second stage compressor (still the cold section) and then through the hot section.
I’m assuming Al meant “cold” as in: the turbofan has a section through which air does not get “hot” i.e. enter the combustor
It’s not that simple.
Turbine blades and disks are air cooled.
Air bled off from the compressor stage.
Turbines are like German cars. You want only the air cooled ones.