Heat Exchangers devices are widely used in air-conditioning, automobiles, chemical process industries, etc. The current demand from industry is to replace conventional heat exchangers with novel complex geometries based compact heat exchangers that achieve requirements such as higher surface area, higher volumetric heat transfer, and limited pressure drop. Triply Periodic Minimal Surface (TPMS) is basically a continuous and non-self-intersecting surface having minimum area between any given 3D boundaries where Gyroid surface is a subset of TPMS. In recent times, numerous studies performed on the heat exchanger based on the cubical Gyroid surface have shown better heat transfer performance when compared with conventional heat exchangers. The complex geometries like Gyroid structure design can be created using additive manufacturing techniques (3D-printing) which is not possible using traditional manufacturing techniques. In this study, novel cylindrical form of the Gyroid surface is explored as a candidate for the heat exchanger to replace the conventional circular tube (CCT).

The investigation of fluid flow and heat transfer characteristics in novel Gyroid tube based heat exchangers is conducted through a two-part numerical analysis. In the initial part, a numerical analysis is performed on the internal fluid flow within a single Gyroid tube, focusing on turbulent flow conditions (4931 ≤ Re ≤ 9863). This phase involves a detailed exploration of the internal fluid flow dynamics and heat transfer characteristics of Gyroid tubes. Furthermore, the study explores the influence of the “C” parameter (0.68 ≤ C ≤ 1.8) on both heat transfer enhancement and pressure drop. Subsequently, in the second part, a numerical study is conducted on a cross-flow heat exchanger comprising a bank of 18 Gyroid tubes. This part of the analysis involves a comparative assessment between the Gyroid tube heat exchanger and a traditional tubular heat exchanger, specifically focusing on thermal performance.

The results show that the maximum Nusselt number of Gyroid tube at C = 1.33 and Re = 9863 is 41.8% higher as compared to CCT at the cost of higher internal pressure drop. The increment in overall heat transfer coefficient of Gyroid cross-flow heat exchanger as compared to traditional tubular heat exchanger is 244%. Additionally, due to the presence of pores outside of the Gyroid tube, the external fluid flowing over the tube gets extra passage which leads to reduction of 67% in pressure drop. Overall, the results show that due to larger surface area and enhanced fluid mixing, the Gyroid tubes show better thermal performance compared to conventional circular tubes.