Numerical Investigation of Flow Dynamics and Heat Transfer in a Baffled Geometry Using Al₂O₃–Water Nanofluid

Abstract

A detailed numerical investigation is carried out to explore the thermal and hydrodynamic behaviour of nanofluid flow through a circular pipe with multiple internal baffles considering axisymmetric geometry. The objective is to understand the mechanisms behind convective heat transfer enhancement using nanofluids in thermally demanding systems. Aluminium oxide (Al₂O₃) nanoparticles suspended in water are used as the working fluid, with varying volume concentrations to assess their impact. The pipe features uniformly spaced baffles to promote secondary flows and thermal mixing. Boundary conditions include a fully developed velocity profile and constant fluid temperature at the inlet, while the pipe wall is maintained at a constant elevated temperature. The simulations are conducted using the Control Volume Method with the SIMPLER algorithm and a power-law scheme. Results show that the presence of nanoparticles significantly improves heat transfer due to enhanced thermal conductivity. However, this benefit is accompanied by increased flow resistance, highlighting a performance trade-off in nanofluid applications.