Improvement in heat transfer rate of a pipe using various types of inserts

Experimental investigations have been carried out with different types of inserts to enhance the heat transfer rate under turbulent flow of air in a pipe. Experimental data obtained using the different types of inserts for friction factor and Nusselt number, and an improvement in heat transfer rate had also recorded. Maximum enhancement in heat transfer is obtained by protruding the spiral-rectangle block inserts. The Performance Assessment Coefficient (PEC) has taken into account to analyze the increment of both the friction coefficient and Nusselt number with and without inserts with respect to flow and heat transfer. The outcome for PEC with different Reynolds number (Re) imply a real increase in Nusselt. The results for PEC with different Re indicate a true increase in the amount of Nusselt is up to 126 percent and the corresponding friction factor is 140 percent with the spiral-rectangle block inserts, in turn subsequent improvement in the heat transfer rate.