Heat transfer by nanofluids in wavy microchannels

Abstract

a b s t r a c tPumping coolants through microchannels with well-defined structures along micro-electronic devices is a typical approach to remove the heat. It has been found recently that so-called nanofluids, i.e. dilute water-Cu or water-Al 2 O 3 suspensions with a particle diameter of 100-150 nm, are highly efficient coolants. Numerical simulations can help to optimize the microchannel structures and typically homogenous single-phase models are applied. However, these underestimate the experimental results. An alternative approach is two-phase models based on an Eulerian approach for the base fluid and a Lagrangian description of the suspended particles. In this paper we follow that route and solve the three-dimensional governing equations including continuity, Navier-Stokes and energy equations with the well-known SIMPLE method. The governing equations for particles are solved by a 4th order Runge-Kutta algorithm. We focus on a wavy microchannel structure and demonstrate that the disagreement between the two simulation approaches is due to the non-homogeneous particle distribution in the domain. We also find that the Nusselt number increases with the increase in volume fraction and the decrease in particle diameter and that it. is about three times higher for a nanofluid in a wavy microchannels as compared to water in a straight microchannels.

Investigation of wavy microchannel ability on electronic devices cooling with the case study of choosing the most efficient microchannel pattern

“…Recently, interrupted, crosscut flow, and non-uniform wavy patterns have been further perused because of improved thermal–hydraulic performance, and some of the prominent studies are found in the following references 29 – 33 . Also, many researches are done on the wavy patterns regarding utilization of the wavy geometries and nanofluids, simultaneously 34 – 36 .…”

A numerical comparison of circular and corrugation heat sink for laminar CuO–water nano-fluid flow and heat transfer enhancement

“…Also reducing the hydraulic diameter can be improved the heat transfer coefficient. Another study using water-Cu and water-Al 2 O 3 nanofluid, heat transfer laminar flow in wavy microchannel with dimensions (10 × 10 × 0.5 mm 3 ), numerically studied by Rostami et al (2018) according to their results the area-heat transfer rate and pressure drop are increased in a wavy microchannel compared to a straight microchannel by 174% and 195.7%, respectively. In comparison with pure water, the area-Nusselt number also increased by about 33.2% for Cu-water of 0.02%, whereas the increase in pressure drop is less than 10.6%.…”

Investigation of Forced Convection Enhancement and Entropy Generation of Nanofluid Flow through a Corrugated Minichannel Filled with a Porous Media

“…Among the proposed procedures for ameliorating the thermal performance in various systems, the utilization of wavy-wall channels is considered to be an efficient approach with the application in heat exchangers, heat sinks, and solar collectors. This issue has been addressed in several investigations [ 2 , 3 , 4 , 5 , 6 , 7 ]. Additionally, the heat transfer in wavy-wall channels have been studied extensively considering their various applications [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ].…”