Thanks TurbineD, Mecaniquito84, DevX!
Well, I have to collect all the information given by everyone!
1)But in your photo, TurbineD, does the apu air bleed go bellow the compressor? Does the APU bleed air turn the fan??
2) But does the fan already start taking air inside? Or does it block something till we start the engine, if not, I imagine that apu bleed air is then only for packs for A/C.
3) If for example, we put thrust TOGA, will they put all the fuel required for TOGA thrust in the combuster or will it keep giving fuel till we reach TOGA thrust? (Well I think it will keep giving fuel, not the entire amount required!)
4) Ok, so the APU bleed air is normal air which goes inside a compressor and then travels inside pipes to finally arrive at the pneumatic engine starter, then the drive box, and turns the main engine rotor. What is the main engine rotor? The fan? So is it the inverse process? The fan turning the compressor and the turbine? So no mixing with fuel for apu bleed air in the combuster?
5) Could anyone show me on a photo, where is the pneumatic engine starter, drive box?