This source may include an airstream entrained with particles which is discharged into {HEAD ~ the space} through {TAIL ~ an orifice}; the airstream diverging as it enters the space 
This source may include an airstream entrained with particles which is discharged into { HEAD ~ the space } through { TAIL ~ an orifice } ; the airstream diverging as it enters the space
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH