Analysis of Transient Laminar Forced Convection of Nanofluids in Circular Channels

2012-11-15
Sert, İsmail Ozan
Sezer Uzol, Nilay
Güvenç Yazıcıoğlu, Almıla
Kakaç, Sadık
In this study, forced convection heat transfer Characteristics of nanofluids are investigated by numerical analysis of incompressible transient laminar flow in a circular duct under step change in wall temperature and wall heat flux. The thermal responses of the system are obtained by solving energy equation under both transient and steady-state conditions for hydrodynamically fully developed flow. In the analyses, temperature dependent thermo-physical properties are also considered. In the numerical analysis, Al2O3/water nanofluid is assumed as a homogenous single-phase fluid. For the effective thermal conductivity of nanofluids, Hamilton-Crosser model is used together with a model for Brownian motion in the analysis which takes the effects of temperature and the particle diameter into account. Temperature distributions across the tube for a step jump of wall temperature and also wall heat flux are obtained for various times during the transient calculations at a given location for a constant value of Peclet number and a particle diameter. Variations of thermal conductivity in turn, heat transfer enhancement is obtained at various times as a function of nanoparticle volume fractions, at a given nanoparticle diameter and Peclet number. The results are given under transient and steady-state conditions; steady-state conditions are obtained at larger times and enhancements are found by comparison to the base fluid heat transfer coefficient under the same conditions.
ASME International Mechanical Engineering Congress and Exposition, (2012)

Suggestions

A numerical study of single-phase convective heat transfer in microtubes for slip flow
Sun, Wei; Kakac, Sadik; Yazicioglu, Almila G. (2007-11-01)
The steady-state convective heat transfer for laminar, two-dimensional, incompressible rarefied gas flow in the thermal entrance region of a tube under constant wall temperature, constant wall heat flux, and linear variation of wall temperature boundary conditions are investigated by the finite-volume finite difference scheme with slip flow and temperature jump conditions. Viscous heating is also included, and the solutions are compared with theoretical results where viscous heating has been neglected. For ...
NUMERICAL ANALYSIS OF CONVECTIVE HEAT TRANSFER OF NANOFLUIDS FOR LAMINAR FLOW IN A CIRCULAR TUBE
Kirez, Oguz; Güvenç Yazıcıoğlu, Almıla; KAKAÇ, SADIK (2012-11-15)
In this study, a numerical analysis of heat transfer enhancement of Alumina/water nanofluid in a steady-state, single-phase, laminar flow in a circular duct is presented for the case of constant wall heat flux and constant wall temperature boundary conditions. The analysis is performed with a newly suggested model (Corcione) for effective thermal conductivity and viscosity, which show the effects of temperature and nanoparticle diameter. The results for Nusselt number and heat transfer enhancement are prese...
Numerical analysis of transient laminar forced convection of nanofluids in circular ducts
Sert, Ismail Ozan; Sezer Uzol, Nilay; Kakaç, Sadik (2013-10-01)
In this study, forced convection heat transfer characteristics of nanofluids are investigated by numerical analysis of incompressible transient laminar flow in a circular duct under step change in wall temperature and wall heat flux. The thermal responses of the system are obtained by solving energy equation under both transient and steady-state conditions for hydro-dynamically fully-developed flow. In the analyses, temperature dependent thermo-physical properties are also considered. In the numerical analy...
EXPERIMENTAL AND NUMERICAL STUDY ON HEAT TRANSFER PERFORMANCE OF SQUARE, CYLINDRICAL AND PLATE HEAT SINKS IN EXTERNAL TRANSITION FLOW REGIME
İnci, Aykut Barış; Bayer, Özgür (2019-01-01)
Geometrical optimization of heat sinks with square, cylindrical and plate fins for heat transfer increase is numerically analyzed in transition regime external flow. The relations between the thermal characteristics of fins and boundary conditions such as free-stream velocity are investigated. Experimental studies are performed by using manufacturable fins to validate the numerical model. Heat transfer correlations are derived in order to determine average heat transfer coefficients over a certain range of ...
Analysis of single phase convective heat transfer in microtubes and microchannels
Çetin, Barbaros; Yüncü, Hafit; Department of Mechanical Engineering (2005)
Heat transfer analysis of two-dimensional, incompressible, constant property, hydrodynamically developed, thermally developing, single phase laminar flow in microtubes and microchannels between parallel plates with negligible axial conduction is performed for constant wall temperature and constant wall heat flux thermal boundary conditions for slip flow regime. Fully developed velocity profile is determined analytically, and energy equation is solved by using finite difference method for both of the geometr...
Citation Formats
İ. O. Sert, N. Sezer Uzol, A. Güvenç Yazıcıoğlu, and S. Kakaç, “Analysis of Transient Laminar Forced Convection of Nanofluids in Circular Channels,” presented at the ASME International Mechanical Engineering Congress and Exposition, (2012), Texas, United States, 2012, Accessed: 00, 2021. [Online]. Available: http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1751496&resultClick=1.