Heat Transfer Enhancement and Hydrodynamic Characteristics of Nanofluid in Turbulent Flow Regime

Abstract EN

Turbulent forced convection of γ-Al2O3/water nanofluid in a concentric double tube heat exchanger has been investigated numerically using mixture two-phase model.

Nanofluids are used as coolants flowing in the inner tube while hot pure water flows in outer tube.

The studies are conducted for Reynolds numbers ranging from 20,000 to 50,000 and nanoparticle volume fractions of 2, 3, 4, and 6 percent.

Results showed that nanofluid has no effects on fully developed length and average heat transfer coefficient enhances with lower slope than wall shear stress.

Comparisons with experimental correlation in literature are conducted and good agreement with present numerical study is achieved.