Experimental study on thermal performance and exergy analysis in an internally grooved tube integrated with triangular cut twisted tapes consisting of alternate wings

Abstract

The present study provides the experimental investigation of thermal performance and exergy analysis in an internally grooved (IG) tube fitted with triangular cut twisted tape insert consisting of alternate wings (TCTT). The analysis is carried out with TCTT for different twist ratio, y = 3.5, 5.3 and 6.5 with attack angle, β = 45° and 90°. The investigations were performed in turbulent regime, with Reynolds number ranging from 3000 to 14,000. The thermal and exergy efficiencies were used to evaluate the overall performance of the heat exchanger, by considering exergy gain and exergy lost. The experimental results reveal that, both the thermal efficiency and exergy efficiency of the IG tube equipped with TCTT were found to be increased up to 1.12 and 1.85 times, respectively, than those that with plain twisted tape (PTT). In this study, the IG tube with TCTT of y = 3.5 and β = 90° achieved maximum PER and exergetic efficiency of 1.35 and 0.634, respectively, at Reynolds number 3000. The empirical correlations were developed from experimental results, to predict the Nusselt number (Nu), friction factor (f) and Performance enhancement ratio (ƞ).