in the present work the effect of cu-water nanofluid, as heat transfer fluid, on the performance of a parabolic solar collector was studied numerically. the temperature field, thermal efficiency, mean-outlet temperatures have been evaluated and compared for the conventional parabolic collectors and nanofluid based collectors. further, the effect of various parameters such as fluid velocity, vol...

The boundary layer flow of Cu-water based nanofluid with heat transfer over a stretching sheet is numerically studied. Second order velocity slip flow model is considered instead of no-slip at the boundary. The governing partial differential equations are transformed into ordinary one using similarity transformation, before being solved numerically. Numerical solutions of these equations are ob...

In the present study, the flow and heat transfer characteristics of a nanofluid in an expanding or contracting porous channel with different permeabilities in presence of thermal radiation are investigated. Analytical solutions for the flow variables are obtained by employing homotopy analysis method (HAM). Maxwell-Garnetts and Brinkman models are considered to calculate the thermal conductivit...

The goal of this paper is to experimentally study the behavior of nanofluid to improve the performance of a circular heat pipe. Pure water and Al2O3-water based nanofluid are used as working fluids. An experimental setup is designed and constructed to study the heat pipe performance under different operating conditions. The effect of filling ratio, volume fraction of nano-particle in the base f...

In the present study, an experimental study is carried out to investigate the effect of adding Al and Cu nanoparticles to the base fluid (water) on the heat transfer rate in a spirally coiled tube. The spirally coiled tube is fabricated from the straight copper tube with the inner and outer coil diameters of 100 and 420 mm, respectively. The experiments have been done for water and two types of...

This paper presents a numerical study of heat transfer to turbulent and laminar Cu/water flow over a backward-facing step. Mathematical model based on finite volume method with a FORTRAN code is used to solve the continuity, momentum, energy and turbulence equations. Turbulence was modeled by the shear stress transport (SST) K–x Model. In this simulation, three volume fractions of nanofluid (0%...

This study investigates a hybrid nanofluid flow towards stagnation region of vertical plate with radiation effects. The consists copper (Cu) and alumina (Al2O3) nanoparticles which are added into water to form Cu-Al2O3/water nanofluid. point describes the fluid motion in solid surface. In this study, both buoyancy assisting opposing flows considered. similarity equations obtained using transfor...

This numerical study investigates the improvement of transient heat transfer in a plain tube using hybrid nanofluids consisting solid particles and twisted tapes with elliptical cuts, under non-uniform flux conditions. The analysis includes calculation Bejan number entropy production. Different working fluids, including water, CuO/water nanofluid, nanofluid 2% volume concentration Al2O3-Cu/wate...

A water-based functionalized nanofluid was made by surface functionalizing the ordinary silica nanoparticles. The functionalized nanofluid can keep long-term stability. and no sedimentation was observed. The functionalized nanofluid as the working fluid is applied in a thermosyphon to understand the effect of this special nanofluid on the thermal performance of the thermosyphon. The experiment ...