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You can also see two ports; the left port is for probing fuel manifold temperature and pressure, and the right is for the igniter (see the ASI section). The fuel sensing port is a 1/8" NPT, and the ASI port is a 1/2-20 ORB.
Fuel comes up from the regen channels and feeds into the injector manifold, and then through the annulus. A small part of the fuel (~15% total fuel mdot) is used as film cooling, and is discharged through the ring of 10 0.5mm holes.
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In the assembly, there is one face seal, which interfaces with the combustion chamber. We were a bit concerned that there would be plastic deformation here when torquing the bolts, as we sized the injector such that the face with the face seal on it contacts the chamber before the injector flange contacts the chamber flange. However, we were able to validate that the lip with the face seal on it would not snap or plastically deform with +/- 0.002" tolerances.
Centerbody
The centerbody inlets N2O at around 600 psi with an ORB fitting (it's an NPT in the photo, but we switched to ORB because ORB superiority). Really though, you should try to minimize the number of NPT fittings going into your injector, as you're probably going to run into a lot of integration issues that will make you uninstall and reinstall injector fittings multiple times.
Pintle Tip
Purpose: Injection of N2O oxidizer into Osiris combustion chamber
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