Its external surface, together with that of the innermost nozzle, creates {HEAD ~ an aerodynamically designed entity} to help enforce {TAIL ~ the swirling action} and the outward speed by using the Coanda effect 
to help enforce
Its external surface , together with that of the innermost nozzle , creates { HEAD ~ an aerodynamically designed entity } to help enforce { TAIL ~ the swirling action } and the outward speed by using the Coanda effect
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH