chapter  5
42 Pages

Heat exchangers

Theirreversibilityofanyheatexchangerisduetotwofactors,thetransferof heatacrossthestream-to-streamtemperaturedifferenceandthefrictionalpressure dropthataccompaniesthecirculationoffluidthroughtheapparatus.Wewilldemonstrateshortlythatthefluidftictionandheattransferirreversibilitycansystematicallybereducedbyslowingdownthemovementoffluidthroughtheheatexchanger. Thistechniqueissynonymouswithemployinglargerheatexchangers,thatis,more heattransferareaandmoreheatexchangervolume.