Sometimes the need for non-circular ducts arises in many heat transfer applications because of lower pressure drop of non-circular cross section such as square duct compared to circular tube, particularly in compact heat. But square cross section has poor heat transfer performance and it is expected that using a nanofluid as a new heat transfer media may improve the heat transfer performance of...

in this paper, mixed convection of al2o3-eg-water nanofluid in a square lid-driven enclosure is investigated numerically. the focus of this study is on the effects of variable thermophysical properties of the nanofluid on the heat transfer characteristics. the top moving and the bottom stationary horizontal walls are insulated, while the vertical walls are kept at different constant temperature...

The present paper discusses the various effects of parameters like particle volume fraction, particle material, particle size, particle shape, particle material and base fluid, temperature, effect of acidity(PH) on thermal conductivity of nanofluids. And also discusses the different mechanisms of heat transfer enhancement like improvement in the thermal conductivity, effect of Brownian motion, ...

In this paper, overall heat transfer coefficient and friction factor of water based γ-Al2O3 nanofluid in a double tube counter flow heat exchanger have been measured experimentally under turbulent flow condition. For better dispersion of γ-Al2O3 nanoparticles in distilled water, magnetic stirrer and ultrasonic vibrator (with a power of 240 kW and frequency of 35 kHz) were implemented. The stabi...

Nanofluid is a new class of heat transfer fluids engineered by dispersing metallic or non-metallic nanoparticles with a typical size of less than 100 nm in the conventional heat transfer fluids.This article aims to investigate the overall and convection heat transfer coefficient and Nusselt number of Al2O3-water nanofluid flowing in a horizontal double pipe heat exchanger under turbulent flow (...

Abstract In this study, a novel lubricant additive nitrogen-doped carbon quantum dot (N-CQD) nanoparticle was prepared by the solvothermal method. The synthesized spherical N-CQD nanoparticles in diameter of about 10 nm had graphene oxide (GO)-like structure with various oxygen (O)- and nitrogen (N)-containing functional groups. Then N-CQDs were added to MoS 2 nanofluid, tribological properties...

The objective of the present study is the synthesis of MWCNT-TiO2 hybrid nanostructures by solvothermal synthesis method with TiCl4 as precursor. The heat transfer enhancement due to the use of MWCNT-TiO2 nanofluid was investigated. As-prepared hybrid materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that MWCNTs were uniformly dec...

The convective heat transfer and pressure drop of water based Al2O3 nanofluid in a horizontal tube subject to constant wall temperature condition is investigated by computational fluid dynamic (CFD) method. The Al2O3 nanofluid at five volume concentration of 0.1, 0.5, 1.0, 1.5 and 2 % are applied as a non Newtonian power law and Newtonian fluid with experimentally measured properties of density...