Several questions.
I'm trying to model the SpaceX Merlin D engine gas generator. Can anyone answer these questions in general?
1 - How much pressure beyond the combustion chamber pressure (9.7 MPa) is needed for injector performance?
2 - What is a good, conservative efficiency for the turbo pumps? I am using 0.8 for both the LOX and RP-1 pumps but they are probably not equally efficient.
3 - What is a good, conservative efficiency for the gas turbine? I am using about 0.394, is that to high? (It's a single shaft system.)
4 - What is a realistic number for the turbine blade temperature? I'm using 1000 deg. C but wonder if that is to low.
Thanks for any help.
aero
You can look for the
Markusic Propulsion presentation (PDF). There's a point scheme of the proposed Merlin 2. Merlin 1 has a chamber pressure of about 1,000psi, and 1D was supposedly 1,400psi. Big TP like the Merlin 2 would be more efficient. But is not a bad starting point.
R7: Thanks for those links. I just had Sutton to date. I like reading the same stuff by different authors. Sometimes author #1 glosses over a 'basic' something that the amateur needs to know, but author #2 does not.