Single-phase fluid flow and heat transfer characteristics of nanofluid in a circular microchannel: Development of flow and heat transfer correlations

2020 ◽  
Vol 234 (18) ◽  
pp. 3689-3708 ◽  
Author(s):  
Mangal Singh Lodhi ◽  
Tanuja Sheorey ◽  
Goutam Dutta
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Reynolds Number ◽  
Fluid Flow ◽  
Friction Factor ◽  
Nanoparticle Concentration ◽  
Heat Transfer Characteristics ◽  
Transfer Characteristics ◽  
Flow And Heat Transfer ◽  
Circular Microchannel

The convective heat transfer in microchannels with the use of nanofluids has proved to be a potential candidate for cooling of micro-electromechanical system devices. The current research article presents the experimental study on fluid flow and heat transfer characteristics of [Formula: see text]/water nanofluid in a microchannel under thermally developing laminar flow at Reynolds number ranging from 300 to 1000. The experimental set-up of a circular microchannel test section with an inner diameter of [Formula: see text] and length of [Formula: see text] is fabricated to conduct the experimental study. The effect of nanoparticle concentration ([Formula: see text]), Reynolds number ([Formula: see text]) on fluid flow and heat transfer characteristics of [Formula: see text]/water nanofluid have been measured and compared with that of distilled water (DW). The results indicate that the maximum enhancement in local heat transfer coefficient is achieved up to [Formula: see text], while friction factor is achieved up to [Formula: see text] for [Formula: see text]/water nanofluid with nanoparticle concentration of [Formula: see text] as compared to DW. The results showed that the performance evaluation criterion of [Formula: see text]/water nanofluid is greater than unity ([Formula: see text]), implying the benefits of nanofluids as compared to DW. Moreover, the predicted data obtained by the present proposed correlations for friction factor and local Nusselt number using [Formula: see text]/water nanofluid show reasonably good agreement with the deviations of [Formula: see text] and [Formula: see text], respectively, with the numerical data as compared to the predicted data obtained by the existing correlations available in the literature.

scholarly journals Numerical investigation of fluid flow and heat transfer characteristics in sine, triangular, and arc-shaped channels

2007 ◽  
Vol 11 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Zakir Hossain ◽  
Sadrul Islam
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Fluid Flow ◽  
Critical Reynolds Number ◽  
Navier Stokes ◽  
Heat Transfer Characteristics ◽  
Single Wave ◽  
Transfer Characteristics ◽  
Flow And Heat Transfer ◽  
Wavy Channels

Time dependent Navier-Stokes and energy equations have been solved to investigate the fluid flow and heat transfer characteristics in wavy channels. Three different types of two dimensional wavy geometries (e.g. sine-shaped, triangular, and arc-shaped) are considered. All of them are of single wave and have same geometric dimensions. Periodic boundary conditions are used to attain fully developed flow. The flow in the channels has been observed to be steady up to a critical Reynolds number, which depends on the geometric configuration. Beyond the critical Reynolds number a self-sustained oscillatory flow has been observed. As a result of this oscillation, there is increased mixing between core and the near-wall fluids, thereby increasing the heat transfer rate. For the same geometric dimensions, flow becomes unsteady at relatively lower Reynolds number in the arc-shaped channel. .

scholarly journals Experimental Study and CFD Modeling of Fluid Flow and Heat Transfer Characteristics in a Mini-Channel Heat Sink Using Simcenter STAR-CCM+ Software

Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 536
Author(s):  
Magdalena Piasecka ◽  
Artur Piasecki ◽  
Norbert Dadas
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Fluid Flow ◽  
Heat Sink ◽  
Numerical Calculations ◽  
Cfd Modeling ◽  
Heat Transfer Characteristics ◽  
Transfer Characteristics ◽  
Flow And Heat Transfer ◽  
Mini Channels

The present work describes an experimental study and CFD modeling of fluid flow and heat transfer characteristics in a heat sink with several asymmetrical heated mini-channels. The data from the experimental research were the basis for numerical calculations. During experiments, the temperature measurement of the outer heater surface was performed by infrared thermography to verify the results of numerical calculations performed in Simcenter STAR-CCM+ software. The main objective was to determine the values of the parameters tested to evaluate the intensity of the heat transfer processes. In the numerical simulations, important variables, mainly the working fluid, heater material, the spatial orientation of the test section, and the number of mini-channels, were assumed. The results of the numerical computations were discussed. Due to simulations, it was possible to indicate which parameters tested in terms of heat transfer turned out to be the most effective. Furthermore, a mesh dependency analysis based on the grid convergence index (GCI) was performed. The residuals, as good indicators of convergence, achieved low values. Generally, the data presented showed satisfactory convergence of the results achieved as a result of the computational procedure.

scholarly journals Effects of Reynolds number, baffle angle, and baffle distance on three-dimensional turbulent flow and heat transfer in a circular pipe

2015 ◽  
Vol 19 (5) ◽  
pp. 1633-1648 ◽  
Author(s):  
Oguz Turgut ◽  
Erkan Kizilirmak
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Nusselt Number ◽  
Friction Factor ◽  
Thermal Performance ◽  
Three Dimensional ◽  
Circular Pipe ◽  
Heat Transfer Characteristics ◽  
Transfer Characteristics ◽  
Flow And Heat Transfer

In this study, steady-state three-dimensional turbulent forced convection flow and heat transfer characteristics in a circular pipe with baffles attached inside pipe have been numerically investigated under constant wall heat flux boundary condition. Numerical study has been carried out for Reynolds number Re of 3000-50,000, Prandtl number Pr of 0.71, baffle distances s/D of 1, 2, and 3, and baffle angle a of 30o-150o. Ansys Fluent 12.0.1 software has been used to solve the flow field. It is observed that circular pipe having baffles has a higher Nusselt number and friction factor compared to the smooth circular pipe without baffles. Maximum Nusselt number and friction factor are obtained for the baffle angle of 90o. Nusselt number increases while baffle distance increases in the range of studied; however, friction factor decreases. Periodically fully developed conditions are obtained after a certain module. Thermal performance factor increases with increasing baffle distance in the rage of studied but decreases with increasing Reynolds number; maximum thermal performance factor is obtained for the baffle angle of 150?. Results show that baffle distance, baffle angle, and Reynolds number play important role on both flow and heat transfer characteristics. The accuracy of the results obtained in this study is verified by comparing the results with those available in the literature for smooth circular pipes. All the numerical results are correlated within accuracy of ?10 and ?15% for average Nusselt number and Darcy friction factor, respectively.

Sign in / Sign up

Export Citation Format

Share Document