Detail of the flat spot on the fuel inlet manifold; on an actual thrust
chamber, there would be a fuel inlet here with a flange onto which the
fuel high pressure duct would be bolted.
Picture 2 of 2.
On this particular test turbopump, I'm not certain where the discharge from the
fuel turbopump was directed. On an actual thrust chamber, 70% of the fuel
would have been directed
down the regenerative cooling tubes comprising the thrust chamber, but of
course this is a truncated thrust chamber
(and many tubes have had sections removed).