It should be appreciated that the heated air in {HEAD ~ the plenum chamber} 28 passes though the inner perforated wall 32 in {TAIL ~ the general direction} of arrow 42  
It should be appreciated that the heated air in { HEAD ~ the plenum chamber } 28 passes though the inner perforated wall 32 in { TAIL ~ the general direction } of arrow 42
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH