Thermal performance of a circular tube embedded with TBVG inserts: an experimental study

The results of various geometrical and flow parameters on thermal energy transfer and performance of tube heat exchangers with solid and perforated "triple-blade vortex generator" insert are presented in this study. Pitch ratio = 1,2,3,4, blade angle = 45 degrees, and perforation index = 0%, 25% are the parameters used in the experiment. The experiments are carried out over a wide range of Reynolds numbers, ranging from 6000 to 24,000. A three-dimensional numerical analysis is also performed to gain a better understanding of fluid flow behavior and heat transfer mechanisms. The results show that using the triple-blade vortex generator insert improves the performance of a heat exchanger. The heat transfer escalation detected in comparison with a simple heat exchanger with a plain tube is in the range of 2.4-4.35, maximum for pitch ratio of 1 and 0% perforation index and a minimum for pitch ratio of 4 and 25% perforation index. The friction factor varies from 0.43 to 3.15, lowest for pitch ratio of 4 and a 25% perforation index and the highest for pitch ratio of 1 and 0% perforation index. The maximum thermal performance of 1.16 is achieved with a pitch ratio of 1 and a perforation index of 25%. For the prediction of Nusselt number, friction factor, and the thermal performance factor of the tubular heat exchanger with triple-blade vortex generator inserts, statistical correlations are developed using experimental data.