Question about Eurofighter structure
Radar mounting bulkhead: this is the vertical plate to which the radar antenna is attached. This is just a structure.  
Strobe light/anti-collision beacon: this is a bright light that flashes to make the aircraft more visible and prevent collisions. 
Engine bleed-air primary heat exchanger: this is a heat exchanger for bleed air from the engine. Bleed air from the engine is hot and needs to be cooled down for various applications, this cooling down is done in the heat exchanger. 


It's quite easy these days to find out what an unknown term means. Just go to Wikipedia and enter the unknown term into the search box.