Heat Transfer Of Hybrid Nanofluid Research Articles

An improvement in heat transfer for rotating flow of hybrid nanofluid: a numerical study

The present study examines the comparison of heat transfer properties of magnetohydrodynamic (MHD) rotating traditional nanofluid with that of developing hybrid nanofluid. A new kind of standard fluid, “hybrid nanofluid” is used to improve heat transfer in boundary layer flow. Silver (Ag) and copper oxide (CuO) nano-size particles are considered to constitute our desired hybrid nanofluid. The rotation of nanofluid is accomplished about the vertical axis so that “angular velocity”, ω∗, is constant. The system of nonlinear and coupled ordinary differential equations is handled using numerical approach BVP-4C with shooting procedure. From the present research, it is noticed that, even in the presence of magnetic field, the rate of heat transfer of hybrid nanofluid (Ag–CuO/water) is higher than that of ordinary nanofluid (CuO/water). In hybrid nanofluid, the required rate of heat transfer can be accomplished by picking distinctive and suitable nanoparticle extents.

Discrete phase numerical model and experimental study of hybrid nanofluid heat transfer and pressure drop in plate heat exchanger

In the present study, numerical as well as experimental investigations have been done on the plate heat exchanger using hybrid nanofluid (Al2O3+MWCNT/water) at different concentration to investigate its effect on heat transfer and pressure drop characteristics. Discrete phase model has been used for the investigation using CFD software and results have been compared with the experimental result as well as result of the homogenous model. Effects of different operating parameters (nanofluid inlet temperature, flow rate and volume concentration) have been studied on coolant outlet temperature, heat transfer rate, convective and overall heat transfer coefficients, Nusselt number, friction factor, pressure drop, pumping power, effectiveness and performance index. Velocity and temperature profiles have been also studied for base fluid, nanofluid and hybrid nanofluid. By using hybrid nanofluid, heat transfer coefficient enhances by 39.16% (merit) with negligible increase in pumping power of 1.23% (demerit). An enhancement in heat transfer and pressure drop characteristics; and hence on the effectiveness of plate heat exchanger has been observed while using hybrid nanofluids instead of base fluid.

Two-phase numerical simulation of hybrid nanofluid heat transfer in minichannel heat sink and experimental validation

Nanofluid cooled mini-micro channel heat sink has become a pleasant alternative for electronics and thermal applications recently due to its compactness and enhanced heat transfer characteristics. In the present study, a numerical simulation on laminar forced convection flow of DI water based Al2O3 nanofluid and Al2O3-MWCNT hybrid nanofluid in minichannel heat sink has been performed using two-phase mixture model to investigate the heat transfer and pressure drop characteristics. The experimental study on hybrid nanofluid flow in minichannel heat sink has also been conducted and validated the numerical model. Effect of some important parameters, such as, hydraulic diameter, channel aspect ratio, composition of Al2O3 and MWCNT in hybrid nanofluid and Reynold number has been investigated as well. Two-phase (heterogeneous) model has good agreement with the experiment result as compared to single phase (homogenous) approach. Maximum heat transfer coefficient has been found for 0.01vol% (Al2O3+MWCNT) (7:3) hybrid nanofluid for minichannel depth of 0.5mm. Pressure drop has been found maximum for minichannel of 0.5mm channel depth. The developing length can increase by using nanofluid. Maximum heat transfer coefficient improvement of 15.6% has been observed with no appreciable increment in pressure drop by using hybrid nanofluids.