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This is the current iteration of the pintle injector, with some dimensions (i.e. number of film cooling holes or number of flange bolts) not calculated yet. Also, the nitrous orifices are not angled yet. However, the final design will most likely closely resemble this, as it is machinable and contains no interpropellant seals.
The pintle center body/ tip is made out of copper, while the baseplate is and centerbody are made out of steel. The interruption in the manifold is so igniter/PT ports can connect to the chamber offset from the holes. As of now, this injector stiffness is still (barely) above 15% for 25% throttle. We haven't accounted for pressure loss in the regen channels yet, but since the fuel and oxidizer will be in separate tanks, the fuel pressure is not reliant on the ox pressure; we can increase the tank fuel pressure to account for the pressure loss in the channels if the fuel turns out to have the limiting stiffness.
Lessons learned from previous iterations:
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