© 2022 by Begell House, Inc.Heat transfer intensification in a tube containing loose-fit twisted tapes with trapezoidal wings was investigated experimentally. The tests were carried out using tapes with four various twist ratios of y/D = 2, 2.5, 3, and 3.5 and four various clearance ratios of c/D = 0.0178, 0.0357, 0.0535, and 0.0718 with the Reynolds number varying between 5000 and 25,000 under constant heat flux conditions. The experimental findings showed that the heat transfer, pressure drop, and thermohydraulic performance increased with a decrease in twist ratio y/D and clearance ratio c/D. The best thermohydraulic performance, 1.52, was offered by twisted tapes with y/D = 2.0 and c/D = 0.0178 at Re = 5000. In conclusion, the correlation of experimental data was obtained by regression analysis, and the deviations found for the Nusselt number, friction factor, and thermohydraulic factor were within ± 5%, ± 12%, and ± 7%, respectively.