This question is about the fuel pump controlled by the hydro-mechanical fuel control unit.
- This is part of a fuel system for a turboprop engine, described on this page which actually comes from a Rolls-Royce book. Full picture for convenience.
I've been staring in vain at this picture for some time, with the hope that something will suddenly become clear:
The pump is supposed to receive low pressure fuel and deliver high pressure fuel at a rate modulated by the FCU using fuel in the purple pipe. The engine speed governor also modulates the pump output.
It seems to be a piston pump, pistons being moved in translation by the rotating plate on the left side, but I'm not even sure, and I don't understand how this increases pressure.
It seems the governor is not rotating... and I don't get the role of the green governor pressure fuel.
Can you help me understanding how it works?
(I've posted all the details I could gather as an "answer").