Zone V comprises {HEAD ~ a set} of {TAIL ~ two axially spaced conventional sprayrings} 72 and 74, sprayring 72 being located upstream of sprayring 74 
Zone V comprises { HEAD ~ a set } of { TAIL ~ two axially spaced conventional sprayrings } 72 and 74 , sprayring 72 being located upstream of sprayring 74
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH