God Bill, this is tricky. Glad I didn't open this can.
Yes, am truly befuddled
Anyone fancy checking some sums whilst I am in the pub tomorrow.
(1) Heat Balance Air
Heat In = Heat Out
Wai + Wa + dPaQa = Wao
TaiCaQa +Wa + dPaQa = TaoCaQa
TaoCaQa - TaiCaQa = Wa + dPaQa
Tao= Tai + Wa/CaQa + dPa/Ca
(2)
LMTD=(Twi - Two) - (Tao - Tai)
---- ln ((Twi - Tao)/(Two - Tai))
Then substituting from (1) :
LMTD=(Twi - Two) - (Wa/CaQa + dPa/Ca)
.... ln((Twi - (Tai + Wa/CaQa + dPa/Ca))/(Two - Tai)
(3) R= F (LMTD)/Wa ,
where F is correction factor (obtainable from Wolverine Fig 4.14 (for two pass) - I think).
Have values for all except the air-flow(Qa) and air's pressure drop(dPa).
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