Mojtaba Shariaty-Niasar

Bio: Mojtaba Shariaty-Niasar is an academic researcher from University of Tehran. The author has contributed to research in topics: Nanofluid & Potassium persulfate. The author has an hindex of 5, co-authored 7 publications receiving 486 citations.

Preparation and application of carbon nanotube nanofluid as a reinforcement of cement slurry

Abstract: The mechanical properties of carbon nanotubes (CNTs) together with their high aspect ratios have drawn intense interest in their potential for use in composite materials. As common cement slurries are not capable of playing a major role in either preventing the degradation of a cement sheath or improving cement stability in cement-to-formation contacts, the idea of designing CNT-reinforced cements with a high Poisson's ratio, shorter thickening time and less free water and fluid loss came to mind. In this research, the properties of CNT–cement composites, which were synthesised by applying multi-wall CNT–water nanofluids in cement slurry, were thoroughly investigated. The results indicated that the Poisson's ratio of CNT–cement composite with 3 wt% multi-wall CNTs is four times greater than that of the unreinforced cement. Moreover, the free water and fluid loss of the former are 97·5% and 85·0% less than that of the latter.

A review on thermophysical properties of nanofluids and heat transfer applications

Abstract: This paper summarizes the important results regarding the improvement in the thermophysical properties of nanofluids. The influence of important parameters like particle's (loading, material, size, and shape), base fluid type, temperature, additives and pH value has been considered. There are many conflicting reports on the influence of parameters on thermophysical properties and the literature in this field is widespread, so this article would be beneficial for investigators to have a precise screening of a broad range of studies in this field. Further literature review of the applications of nanofluids with a particular focus on the advantages of using nanofluids in solar collectors and as coolants in automotive heat exchangers. The authors hope that this review can help in the translation of nanofluid technology from the lab scale research to industrial applications in solar collectors and automotive sector. At last, the paper identifies the opportunities for future research.

Investigation of thermal conductivity and rheological properties of nanofluids containing graphene nanoplatelets

Abstract: In the present study, stable homogeneous graphene nanoplatelet (GNP) nanofluids were prepared without any surfactant by high-power ultrasonic (probe) dispersion of GNPs in distilled water. The concentrations of nanofluids were maintained at 0.025, 0.05, 0.075, and 0.1 wt.% for three different specific surface areas of 300, 500, and 750 m2/g. Transmission electron microscopy image shows that the suspensions are homogeneous and most of the materials have been well dispersed. The stability of nanofluid was investigated using a UV-visible spectrophotometer in a time span of 600 h, and zeta potential after dispersion had been investigated to elucidate its role on dispersion characteristics. The rheological properties of GNP nanofluids approach Newtonian and non-Newtonian behaviors where viscosity decreases linearly with the rise of temperature. The thermal conductivity results show that the dispersed nanoparticles can always enhance the thermal conductivity of the base fluid, and the highest enhancement was obtained to be 27.64% in the concentration of 0.1 wt.% of GNPs with a specific surface area of 750 m2/g. Electrical conductivity of the GNP nanofluids shows a significant enhancement by dispersion of GNPs in distilled water. This novel type of nanofluids shows outstanding potential for replacements as advanced heat transfer fluids in medium temperature applications including solar collectors and heat exchanger systems.

An experimental study on the effect of diameter on thermal conductivity and dynamic viscosity of Fe/water nanofluids

Abstract: The addition of nanoparticles to a base fluid is one of the significant issues to enhance heat transfer. In this study, different nanofluids were developed by mixing a water base fluid with magnetic nanoparticles. Thermophysical properties such as thermal conductivity and viscosity of the obtained nanofluid were investigated. The effect of different nominal diameters of nanoparticles and concentrations of nanoparticles on the thermal conductivity and viscosity of nanofluids have been examined. Three different diameters of magnetic nanoparticles (about 37 nm, 71 nm, and 98 nm) have been tested in this experimental investigation. Experimental results indicate that thermal conductivity increases as volume fraction increases, and thermal conductivity of the nanofluid increases with a decrease of nanoparticle’s size. Moreover, the nanofluid dynamics viscosity ratio increases with an increase in particle concentration and nanoparticle’s diameter. This paper identifies several important issues that should be considered in future work.