Thermohydraulic performance of a helical heat exchanger: an experimental study on the synergistic effects of novel combined nano-SiO2 and anionic PAM in aqueous solutions and correlation establishment

Enhancing heat transfer rates while concurrently reducing pressure drop will significantly enhance the energy efficiency of industrial heat exchangers, thereby contributing to a cleaner and more sustainable environment in the future. This study explores the fluid flow of a novel combination solution in a helical heat exchanger under a constant heat flux across various Reynolds numbers (5000–17000) aiming to uncover synergies that enhance heat transfer efficiency while reducing drag for the first time. Two key performance metrics, namely Drag Reduction (DR) and Heat Transfer Enhancement (HTE), along with the thermal effective index, are introduced to evaluate both hydrodynamic and thermal characteristics. Under turbulent conditions, an aqueous solution containing Anionic PAM (100–500 ppm) obtains a noteworthy 43