Nanofluids are colloidal suspensions of nanosized particles in the conventional base fluid such as water, engine oil and ethylene glycol. The nanoparticles include the chemically stable metals, metal oxides and nonmetallic. In the present study, the literature available on the applications of nanofluids in plate heat exchanger have been compiled and reviewed. However, this paper elaborates the ...

Reverse micellar systems are nanofluids with unique properties that make them attractive in high selectivity separation processes, especially for biological compounds. Understanding the phase behavior and thermodynamic properties of these nanosystems is the first step in process design. Separation of components by these nanosystems is performed upon contact of aqueous and reverse micellar phase...

Nanofluids, colloidal suspensions consisting of base fluids and nanoparticles, are a new generation of engineering working fluids. Nanofluids have shown great potential in heat/mass transfer applications. However, their practical applications are limited by the high production cost and low stability. In this study, a low-cost agricultural waste, rice husk ash (RHA), was used as a silicon source...

An investigation on viscosity was conducted 2 weeks after the Al2O3-water nanofluids having dispersants were prepared at the volume concentration of 1-5%. The shear stress was observed with a non-Newtonian behavior. On further ultrasonic agitation treatment, the nanofluids resumed as a Newtonian fluids. The relative viscosity increases as the volume concentrations increases. At 5% volume concen...

To effectively predict the thermal conductivity and viscosity of alumina (Al₂O₃)-water nanofluids, an artificial neural network (ANN) approach was investigated in the present study. Firstly, using a two-step method, four Al₂O₃-water nanofluids were prepared respectively by dispersing different volume fractions (1.31%, 2.72%, 4.25%, and 5.92%) of nanoparticles with the average diameter of 30 nm....

In this study we present new data for the thermal conductivity enhancement in four nanofluids containing 11, 25, 50, and 63 nm diameter Aluminum oxide (Al2O3) nanoparticles in distilled water. The nanofluids were prepared using single step method (that is, by dispersing nanoparticle directly in base fluid) which was gathered in ultrasonic device for approximately 7 h. The transient hot-wire las...

In this study, the lipophilic Cu nanoparticles were synthesized by surface modification method to improve their dispersion stability in hydrophobic organic media. The oil-based nanofluids were prepared with the lipophilic Cu nanoparticles. The transport properties, viscosity, and thermal conductivity of the nanofluids have been measured. The viscosities and thermal conductivities of the nanoflu...

This paper presents an investigation on the potential tribological properties of the waterbased cerium dioxide nanofluids. The nanofluids with different nanoparticle concentrations were prepared in a materials laboratory. A stable dispersion of nanoparticles in the fluids was achieved with an appropriate percentage of surfactant sorbitan monostearate. The stability of particle dispersion was st...

In this study, nanofluids of Chromium (Cr) in water, Ethylene Glycol and Ethanol have been prepared using single step method. The thermal conductivity and diffusivity of these nanofluids were measured via hot wire-photothermal deflection technique. Based on finite difference method (FDM) temperature distribution and photothermal deflection caused by the hot wire inside nanofluids was obtained. ...

The thermal conductivity of boron nitride/ethylene glycol (BN/EG) nanofluids was investigated by transient hot-wire method and two abnormal phenomena was reported. One is the abnormal higher thermal conductivity enhancement for BN/EG nanofluids at very low-volume fraction of particles, and the other is the thermal conductivity enhancement of BN/EG nanofluids synthesized with large BN nanopartic...