The Exergy Optimization of a Flat-Plate Solar Collector Using AL2O3-Water, CuO-Water and TiO2-Water Nanofluids by Genetic Algorithm

Thermal Property Measurement of Al2O3-Water Nanofluids

Preparation of CuO/Water Nanofluids Using Polyvinylpyrolidone and a Survey on Its Stability and Thermal Conductivity

In this article CuO/water nanofluid was synthesized by using polyvinylpyrolidone (PVP) as the dispersant.  Thenanofluid stability period and the heat transfer enhancement were determinedby measuring the thermal conductivities. To study the nano-fluid stability, zeta (ζ) potential, and absorbency were measured under different pH values and PVP surfactant concentrations; also thermal conductivity...

An experimental investigation on the performance of a symmetric conical solar collector using SiO2/water nanofluid

One of the effective methods to improve the thermal efficiency of solar collectors is using nanofluids as the coolant. The present study experimentally investigated the effect of SiO2/water nanofluid with 1% mass fraction on the performance of a symmetric collector, i.e. conical solar collector. The conical solar collector with 1 m2 area and normal to the earth was tested in Ahvaz, a city in th...

Viscosity affected by nanoparticle aggregation in Al2O3-water nanofluids

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...

Nucleate Pool Boiling Heat Transfer to Al2O3-Water and TiO2-Water Nanofluids on Horizontal Smooth Tubes with Dissimilar Homogeneous Materials

Nucleate pool boiling heat transfer coefficients of Al2O3-water and TiO2-water nanofluids have been experimentally measured on three horizontal tubes with different materials and similar roughness under atmospheric pressure. Results revealed that the presence of nanoparticles in the base fluid leads to an increase in pool boiling heat transfer coefficients on stainless steel and brass tubes in ...

Exergy Analysis of Flat Plate Solar Collectors

This study proposes the concept of the local heat loss coefficient and examines the calculation method for the average heat loss coefficient and the average absorber plate temperature. It also presents an exergy analysis model of flat plate collectors, considering non-uniformity in temperature distribution along the absorber plate. The computation results agree well with experimental data. The ...