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Here is pretty good video that explains (among other things) Full Flow Staged Combution cycle:
Quote from: spacenut on 07/27/2017 01:23 pmWhere does SpaceX test this sub-scale engine? Will they attempt to see what it's maximum thrust can be?Also, can they test a full scale engine at McGregor? Or do they need Stennis? SpaceX tests their subscale Raptor at their McGregor test facility in Texas. I think that they will also test the full size Raptor at McGregor as well.
Where does SpaceX test this sub-scale engine? Will they attempt to see what it's maximum thrust can be?Also, can they test a full scale engine at McGregor? Or do they need Stennis?
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Based on IAC 2017, we are now looking at much smaller Raptor, roughly 60% of IAC 2016.31 engines with 5400mT thrust. That's 1707kN per engine.And the chamber pressure now down to 250barIAC 2016, it was 300bar, 3050kN
Still thinking they'll go up to 300 eventually.
Saves a lot in dev. costs over IAC2016 size Raptor but I still think they still should have bit the bullet and gone with a larger Raptor to reduce booster engine no.
Quote from: titusou on 09/29/2017 08:46 amBased on IAC 2017, we are now looking at much smaller Raptor, roughly 60% of IAC 2016.31 engines with 5400mT thrust. That's 1707kN per engine.And the chamber pressure now down to 250barIAC 2016, it was 300bar, 3050kNSo looks like what was termed subscale Raptor that is undergoing testing is now the size of Raptor they will use. Saves a lot in dev. costs over IAC2016 size Raptor but I still think they still should have bit the bullet and gone with a larger Raptor to reduce booster engine no.
The test data given was a bit of a surprise to me. I had no idea they had progressed so much already!
Quote from: Dante80 on 09/29/2017 10:57 amThe test data given was a bit of a surprise to me. I had no idea they had progressed so much already!Appears they need more or larger tanks if they can only get a 40 sec run. Theyll need a lot more time running the Raptor.The blue exhaust and shock diamonds were fantastic. Still have a hard time imagining 31 of them on a vehicle.
I'm pretty sure this version of the Raptor will eventually produce 3 MN. Initially Merlin 1D had ~70% of block 5 levels; here's the difference is roughly the same.
For my personal understanding, is it correct that the change in mixture ratio makes the combustion colder, hence less pressure and ISP?Also, can someone please explain to me why they are going oxygen rich instead of fuel rich? I always thought a fuel rich environment would create lighter combustion elements, hence higher ISP for the same chamber temperature and pressure. Is that wrong?
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