Design And Other Factor Involved In The Fabrication Of Heat Exchanger Experimentation Setup.

Abstract

This review paper deals with the use of modified twisted tape inserts as Passive Heat transfer Augmentation
device. Effect of Reduced width twisted tape (RWTT), Baffled Reduced width twisted tape (BRWTT1) & Baffled Reduced
width twisted tape with holes (BRWTT2) on heat transfer and friction factor for heating of water for Reynolds number range
2500-30000, was studied experimentally in a double pipe heat exchanger. Based on constant flow rate, the heat transfer
coefficient were found to be 1.18-3.66, 2.61-7.07 & 3.58-8.08 times the smooth tube values for RWTT, BRWTT1 & BRWTT2
respectively. The friction factor values were found to be 3.23-5.96, 7.79-11.23 & 8.86-14.44 times the smooth tube values for
RWTT BRWTT1 & BRWTT2 respectively. Based on constant pumping power, the heat transfer coefficient values were found
to be 0.88-1.62, 1.59-3.70 & 2.12-4.49 times the smooth tube values for RWTT, BRWTT1 & BRWTT2 respectively. Based on
the increase in Heat transfer coefficient, Performance evaluation criteria R1 & R3, it was concluded that Baffled Reduced
width twisted tape & Baffled Reduced width twisted tape with holes performs much better than the Reduced width twisted
tapes(RWTT) of the same twist ratio. Whenever inserts are used for the heat transfer enhancement, along with the increase in
the heat transfer rate, the pressure drop also increases. This increase in pressure drop increases the pumping cost. Thus it’s
highly essential not to allow the pressure drop to go beyond a specified value while going for heat transfer enhancement
techniques using inserts.