Abstract
In this paper, effects of temperature-dependent thermophysical properties on laminar forced convection effectiveness of Al2O3–water nanofluids in a circular tube imposed to a constant heat flux are investigated numerically. The numerical study is supplemented with a scale analysis based on the integral energy equation. The analysis is conducted for various inlet temperatures and considering two cases for properties including (i) constant-properties, and (ii) temperature-dependent properties. The simulated results are presented for three different concentrations of nanofluids i.e. 0%, 5%, and 9%, volume flow rates in the range of 24–180cm3/min which correspond with Reynolds numbers between 120 and 2000, heat fluxes between 5.51×102 and 1.23×104W/m2, and various inlet temperatures in the range of 25–50°C. The effects of various inlet temperatures of nanofluids and different thermophysical models on the local and average Nusselt numbers in the tube have been investigated in details. It is found that with an increase in both nanofluid concentration and temperature rise in the heated section, the effects of inlet temperature and thermophysical properties on the Nusselt number are more pronounced.
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.
