The combustion heat generated during {TAIL ~ incineration} of the waste gas mixed with {HEAD ~ the air} establishes strong buoyancy and produces a swirling air stream 
The combustion heat generated during { TAIL ~ incineration } of the waste gas mixed with { HEAD ~ the air } establishes strong buoyancy and produces a swirling air stream
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH