Comparative study on thermal performance of helical screw tape inserts in laminar flow using Al2O3/water and CuO/water nanofluids

This paper presents a comparison of thermal performance of helical screw tape inserts in laminar flow of Al₂O₃/water and CuO/water nanofluids through a straight circular duct with constant heat flux boundary condition. The helical screw tape inserts with twist ratios Y = 1.78, 2.44 and 3 were used in the experimental study using 0.1% volume concentration Al₂O₃/water and CuO/water nanofluids. Nanofluids with required volume concentration of 0.1% were prepared by dispersing specified amounts of Al₂O₃ and CuO nanoparticles in deionised water. The performance analysis of helical screw tape inserts in laminar flow of Al₂O₃/water and CuO/water nanofluids is done by evaluating thermal performance factor for constant pumping power condition. Thermal performance factor of helical screw tape inserts using CuO/water nanofluid is found to be higher when compared with the corresponding value using Al₂O₃/water. Therefore, the helical screw tape inserts show better thermal performance when used with CuO/water nanofluid than with Al₂O₃/water nanofluid.