Experimental studies on hydrodynamic behaviour of flow through a tube with Triangular Wavy Tapes (TWT)

Abstract

The present project work includes the introduction of TWT as inserts as passive augmentation device for tube side liquid flow.The effect of turbulence on friction factor was measured and compared with the values for smooth tube.The effect of baffles was also taken into account and again a comparative study was made on the basis of varying the baffle spacing.All the results and readings were compared with the standard data from the smooth tube.Whenever inserts are used for the heat transfer enhancement,both the heat transfer rate and the pressure drop increse.This increse in pressure drop increases the pumping cost.Thus it is highly essential not to allow the pressure drop to go beyond a specified value while going for heat transfer enhancement techniques using inserts. Experimental work on hydrodynamic behaviour using TWT is executed.Inserts when placed in the path of the flow of the liquid,both the heat transfer rate and the pressure drop increase, because of increased degree of turbulence created.The present study includes the determination of friction factoe for various TWT and its ten modifications.In the beginning,we conducted the experiment without any insert to get the value for plain tube and thereafter the experiment was repeated with TWT without any baffles and with baffleswith varying baffle spacing.The results of TWT without any baffles and with baffles with varying baffle spacing have been comparedwith values for the smooth tube.It was also observed that with an increase in Reynolds number (Re),the friction factor decreases.The highest value for fa/f0 was found to be around 12.