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