Comparative studies on thermal performance of spiraled rod inserts in laminar flow with nanofluids

Abstract

The enhancement of heat transfer is primarily accomplished by nanofluids and inserts. In this study, the effect of spiralled rod inserts (SRIs) with three different kinds of nanofluids on thermal performance is investigated experimentally. Al2O3, CuO, and TiO2 nanoparticles are used. Two SRIs with different pitch sizes are used in this study (50 mm pitch, SRI-1 and 30 mm pitch SRI-2). Al2O3, CuO, and TiO2 nanoparticles are mixed with deionised (DI) water to make nanofluids. Two volume concentrations (VCs) (0.1 and 0.2%) of nanofluids are used. The Nusselt number rises by 11.4, 25.3, and 4.0%, respectively, for Al2O3, CuO, and TiO2 nanofluids having 0.2% VC in the smooth tube. Using Al2O3, CuO, and TiO2 nanofluids having 0.2% VC with SRI-2 improves the Nusselt number (Nu) by 29.6, 43.4, and 23%, respectively. The SRI-2 combined with CuO nanofluid having 0.2% VC produces a greater thermal performance factor (1.34).