RS25 Test Video

[Linear]

Carrying on from January's tests, yesterday saw another test of the RS25/('new' SSME) engine that will be used on the SLS.

[Hcube]

I myself wouldn't have left my car this close... Thanks for sharing

What's the temperature of the bell during engine operation ? I can see it become white as the burn goes on... is that condensation solidifying ? I understand it is cooled by the LH2, and that the chamber temperature is very high... What are the results of this temperature difference ? Doesn't the LH2 become gaseous during the process ?

[Camacha]

I would like to add this video. It might very well be the engine tested.

[SciMan]

Just to be clear, we are talking about the RS-25E, right?

Also, I assume the E stands for Expendable, right? Obviously, the SLS core stage's engines aren't going to be much good for anything once they hit the ocean.

[J.Random]

Beautiful.

[Hcube]

Digging this thread up : new RS-25 Engine test ! it happened on June 11th.

Now *THAT* is a very long burn for a first stage engine. MECO looks a bit rough though.

I can already imagine four of these roaring off towards space...

[Kryten]

Just to be clear, we are talking about the RS-25E, right?

The engines currently tested are RS-25Ds. The tests are of new controllers they're being fitted with, and higher inlet pressure and lower LOX temperatures associated with use on SLS.

Edited June 16, 2015 by Kryten

[RandomRyan]

Blimey, its a beauty!

[Starwhip]

Can we get a noise like that for engines in KSP?

Yeah, I'd also like to know why it turns white.

[Columbia]

Oh gawd! It feels.. so.. loud and screamy.. I like it. *maniac grin

In all seriousness, that looked and sounded epic.

[Ignath]

Yeah, amazing sounds coming from that beast! So much condensation/exhaust smoke too...bet it rains shortly after that test.

[Hcube]

Yeah, I'd also like to know why it turns white.

AFAIK :

The temperatures inside the combustion chamber and nozzle are crazy high. Pretty much no materials can survive those temperatures for a 8minutes burn like this one. So what happens here (and happened in the space shuttle) is that you make small pipes inside the nozzle. The cold (very freaking cold) LH2 comes from the tank and passes through these pipes before going into the combustion chamber, and that cools off the engine. this is why liquid fuel engines are often very complex with a lot of piping and plumbing

Now, that makes the outside of the nozzle crazy cold, and condensation forms on its surface, and then it solidifies into ice.

[RandomRyan]

Yeah, I'd also like to know why it turns white.

Mach Diamonds.

[Hcube]

Mach Diamonds.

Are we talking about the exhaust being white or the nozzle being white here ?

(Cause as far as i know shock diamonds in the exhaust won't make the nozzle white )

[RandomRyan]

sorry i accidentally read why as what and not the nozzle

(i thought he was talking about the thing down there)

[okan170]

Yeah, amazing sounds coming from that beast! So much condensation/exhaust smoke too...bet it rains shortly after that test.

Yup, all the exhaust is just water vapor so those clouds are basically just low rainclouds.