Simulation of vortices and numerical evaluation of heat transfer using multiwalled carbon nanotubes-based hybrid nanofluid for viscous flow sensor

ABSTRACT

In this paper, we aim at the simulation of setup for vortex generation and measurement. This project will lead to designing the experimental setup to create vortices and development of heat flow sensors. The working fluid for the vortex generator is hybrid nanofluid such as Iron (III) Oxide-MWCNT and propanol. The usage of these hybrid fluids was considered due to their better physical and chemical properties compared to water and other conventional fluids. Ansys Fluent was used to simulate the experiment. Viscosity of the fluid increases for both hybrid nanofluids, from inlet to outlet by a magnitude of 10 times (for Fe₃O₄ + MWCNT: 5.3 × 10⁻⁵ Pa.s to 6.3 × 10⁻⁴ Pa.s; for Al₂O₃ + MWCNT: 7.5 × 10⁻⁵ Pa.s to 6.5 × 10⁻⁴ Pa.s), for laminar flow (Reynolds number = 400). Vortex generation increases the viscosity of the hybrid mixture but not water (for water, it stays constant across the channel at 4.9 × 10⁻⁴ Pa.s). Vortex induced viscosity is seen in hybrid mixtures. Strain thinning due to vortex formation is not observed, therefore the behavior of the mixtures is along the lines of Newtonian fluids.

GRAPHICAL ABSTRACT

In this paper, we aim at the simulation of setup for vortex generation and measurement. This project will lead to designing the experimental setup to create vortices and development of heat flow sensors. The working fluid for the vortex generator is hybrid nanofluid such as Iron (III) Oxide-MWCNT and propanol. The usage of these hybrid fluids was considered due to their better physical and chemical properties compared to water and other conventional fluids.

Ansys Fluent was used to simulate the experiment. Viscosity of the fluid increases for both hybrid nanofluids, from inlet to outlet for laminar flow (Reynolds number = 400). Vortex generation increases the viscosity of the hybrid mixture but not water. Vortex induced viscosity is seen in hybrid mixtures. Strain thinning due to vortex formation is not observed, therefore the behavior of the mixtures is along the lines of Newtonian fluids.

KEYWORDS:

• Nanofluids
• viscosity
• flow
• sensor

Acknowledgments

The authors express their gratitude to management of Ramaiah Institute of Technology for their encouragement and support.

Disclosure statement

No potential conflict of interest was reported by the author(s).