3D-Printed Engine Tests: What Is A Breadboard Engine?

NASA has been working with various vendors to make 3D-printed parts, such as turbopumps and injectors, and test them individually. To test them together, they connected the parts so that they work the same as they do in a real engine, only they are not packaged together in a configuration that looks like the typical engine you see on a test stand. "In engineering lingo, this is called a breadboard engine," explains NASA propulsion engineer Nick Case, the testing lead for the effort. "What matters is that the parts work the same way as they do in a conventional engine and perform under the extreme temperatures and pressures found inside a rocket engine. The turbopump got its 'heartbeat' racing at more than 90,000 revolutions per minute and the end result is the flame you see coming out of the thrust chamber to produce over 20,000 pounds of thrust, and an engine like this could produce enough power for an upper stage of a rocket or a Mars lander."

Transcript

00:00:00 hi I'm Nick case and I work here at Marshall space flight center in the propulsion Systems Department and today I'm going to talk to you about our adely manufactured demonstrator engine that we currently have built up here at testan 116 this is what we call a breadboard engine configuration and so a lot of it is all spread out uh to give us more room to

00:00:20 put instrumentation and uh specific sensors to try to get as much data as we can on our addly manufactured parts and I'll start off with our fuel turbo pump so this uh pump is for liquid hydrogen uh and that is at- 423 de F and it produces over 2,000 horsepower spins at 990,000 RPM and uh the majority of all these parts here are addly manufactured the

00:00:48 only things that we don't have are seals and bearings uh and we just completed 15 tests on this uh this uh component and now we're ready to incorporate it into the engine over here we have our main fuel valve and so what this uh this valve does is allows the liquid hydrogen coming out of the turbo pump into our mixer which is also addly manufactured and we are able to mix

00:01:10 liquid hydrogen and gaseous hydrogen together to uh send into our injector which is behind here that injector is also addly manufactured and it's one of the largest injectors that we've ever uh we've ever printed here at Nasa on the back side of the injector is our ablative chamber uh and this will allow us to do a short duration test um and it's uh pretty

00:01:33 cheap to make and uh and and helps us with schedule and so we'll we'll use that for our first test series we also have a a regeneratively cooled chamber that is uh being 3D printed right now that we'll use for a later test series over here on the other side is our oxygen system and uh it starts with the U the main oxidizer valve back here which is 3D printed we currently don't

00:01:56 have a oxygen pump on the system that's currently being built right now uh we're using our our our pressurized tanks in the facility to provide our our flow for the oxygen system Downstream of that is our turbine bypass and turbine discharge valve which will take the uh gaseous hydrogen from the turbine and discharge it out uh through this nozzle for uh for our test program and so this this valve

00:02:22 and this this bowl are both 3D printed so overall this adely manufactured demonstrator engine uh contains over 75% atively manufactured Parts uh for a future rocket engine design and we intended to test this breadboard engine uh for a total of 10 tests in liquid hydrogen and liquid oxygen and in the future we'll do 10 tests in liquid methane and liquid oxygen