NUMERICAL INVESTIGATION OF HEAT TRANSFER AND TURBULENT FLUID FLOW FOR TRANSVERSE VORTEX GENERATORS WITH NANOPARTICLES

This paper proposes a simple design and easy-to-install vortex generator (VG) for heat exchangers to enhance heat transfer rates. The aim is to maintain low pressure drops and high heat transfer rates. The effects of the VG's geometrical parameters on thermal performance and pressure drop are investigated in this paper for divergent and convergent schemes using commercial software Comsol Multiphysics version 6. The effects of Reynolds number, VG angle, and the quantity of VGs on the response (i.e., Nusselt number and pressure drop) are investigated based on variance analysis. The nanoparticle concentration varies from 1 to 6%. The results indicate that the quantity of VGs is the most significant factor affecting pressure drop. The critical factor for heat transfer enhancement of divergent and convergent VGs are the Reynolds number and the quantity of VGs, respectively. Finally, the optimal conditions are predicted by the response surface methodology (RSM). The optimal requirements for using VG type A are beta = 0 degrees, the quantity is two, and the Reynolds number should be 9160. Furthermore, the optimal conditions for VG type B are beta = 0 degrees, Reynolds number is 10,000, and the number of VGs is two. The VG proposed in this study has a simple structure that can be efficiently designed and installed on heat exchangers. It is more efficient and applicable than the designs suggested in the literature.