Aerothermal performance improvement by array of pin-fins with spiral wings

Abstract An innovative array of pin-fins with spiral wings was proposed as a new heat transfer augmentation device. The aerothermal characteristics were correlatively analyzed based on the Nusselt number measurements and the concomitant augmentations in friction factors and the turbulent flow field simulated by the commercial code at the Reynolds numbers of 5500, 7500, 10,000, 15,000, and 20,000. The pair of spiral wings on each cylindrical pin between two neighboring pins in a pin-row swirled the flows to promote the core-to-wall fluid mixings. The endwall average Nusselt numbers and fiction factors were raised to 5.4–5.03 and 107.6–114.93 times of the plain tube references when 5500 ≤ Re ≤ 20,000. Compared with the ducted flows with the various pin fin geometries, the array of pins with the spiral wings achieved the higher degree of heat transfer elevations with the noticeable pressure drop augmentations. The empirical correlations that calculated the endwall-average Nusselt number and Fanning friction factor of the channel with the spirally finned pin array were generated.