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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.
There is a tee fitting upstream of the centerbody that gives us nitrous manifold pressure. It's probably a somewhat rough estimate as the flow has to constrict a lot more before it exits via the pintle orifices, but since our control loop controls nitrous mdot indirectly through pc measurement, it doesn't really need to be that accurate.
Pintle Tip
Purpose: Injection of N2O oxidizer into Osiris combustion chamber
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