Heat transfer enhnacment in a circular tube fitted with new twisted tape insert with rings

This study investigates the impact of using new twisted tape (TT) inserts with rings on the Nusselt number (Nu) and friction factor (f) for heat exchangers, air intercoolers and for other thermofluidics applications. The analysis compares the effects of air and water as cooling fluids. Experimental setup is used to obtain experimental data needed for a Computational Fluid Dynamics (CFD) validation. Then the CFD model is used to predict the impact of using the new TT insert with rings compared with the conventional TT without rings under various conditions which can’t be attained by the experimental facilities at the lab scale. The obtained results showed that the new proposed TT insert with rings significantly enhances heat transfer efficiency while maintaining acceptable pressure drops. The findings suggest incorporating TT with rings can optimize heat transfer performance in various heating and cooling applications. The experimental results showed that adding the rings to the TT enhances the heat transfer characteristics compared with the TT without rings, especially at larger TT pitch distances. Further, the experimental results showed that the Nu values in the case of using the TT inserts with rings significantly increased by up to 25% more than smooth pipes at low air velocities with larger pitch distance and by about 43% at higher velocities with smaller pitch distance. However, this increase in heat transfer also led to a rise in the friction factor, which went up to four times higher at low velocities and larger pitch distances and up to seven times higher at greater velocities and smaller pitch distances.