ABSTRACT

This research work uas carried out to study the effect of swirler vane angles on heat transfer characteristics in turbulent pipe flow. Vane suirlers were inserted at the entrance of the main tube to swirl the air flowing in the test section. Also,the effect of vane suirlers uith sudden tube enlargement uas studied. The flowing air uas heated by means of electric heaters wound round the main tube so as to give a uniform heat flux.
The augmentation in heat transfer due to different vane angles and different enlargement ratios uas represented by the increase in Nusselt number. Relations for this increase,pressure drop and thermal entry length for various entry conditions were obtained.