Engine Refresher
barit1 raises an interesting point concerning the pressure to be overcome by the HP engine fuel pumps at the burner nozzles at low thrust. This could be expected to be the addition of the engine core compressor output and the back pressure from the turbine/s which would not be inconsiderable. My guess would be about 100 to 200 psi.
Does anyone have a typical pressure plot through the engine core at low thrust or the range of air pressures at the burner nozzles over the thrust range at low altitude?