Abstract
Laminar mixed convection of a nanofluid consisting of water and Al2O3 in an inclined tube with heating at the top half surface of a copper tube has been studied numerically. The bottom half of the tube wall is assumed to be adiabatic (presenting a tube of a solar collector). Heat conduction mechanism through the tube wall is considered. Three-dimensional governing equations with using two-phase mixture model have been solved to investigate hydrodynamic and thermal behaviours of the nanofluid over wide range of nanoparticle volume fractions. For a given nanoparticle mean diameter the effects of nanoparticle volume fractions on the hydrodynamics and thermal parameters are presented and discussed at different Richardson numbers and different tube inclinations. Significant augmentation on the heat transfer coefficient as well as on the wall shear stress is seen.
Highlights
Many different industries such as electronic, automotive and aerospace have been facing heat transfer limitation for improving performance of their thermal systems
The results presented here are for different Richardson numbers and three nanoparticle volume fractions
For a given nanoparticle mean diameter and concentration the effect of tube inclinations on the secondary flow vector and dimensionless temperature are shown in Figure 5 for two different Richardson numbers
Summary
Many different industries such as electronic, automotive and aerospace have been facing heat transfer limitation for improving performance of their thermal systems. Effective viscosity is calculated by the following equation proposed by Masoumi et al [15] which considers the effects of volume fraction, density and average diameters of nanoparticle and physical properties of the base fluid: μeff μf ρp × Vbd2p 72Cδ. Boundary condition This set of nonlinear elliptical governing equations has been solved subject to the following boundary conditions: At the tube inlet (Z = 0): Vmz = V0, Vmr = Vmθ = 0, T = T0. The numerical procedure is reliable and can well predict developing mixed convection flow in a tube
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
