An Experimental Study of Forced Convective Fluid Flow in Divergent Minichannels Using Nanofluids

Abstract

An experimental investigation was conducted to study the heat transfer and pressure drop characteristics of an array of divergent straight minichannels (DSM) and was compared with straight minichannels (SM). The experiment was conducted in hydro dynamically developed and thermally developing laminar and turbulent regimes. The minichannel heat sink array consisted of 15 rectangular channels machined on a 30x30mm2and 11mm thick Aluminium substrate. Each minichannel was of 0.9mm width, 1.8mm pitch and a depth of 1.3 mm at entrance and 3.3 mm at exit for increasing the cross sectional area. DI water and 0.5% and 0.8% volume concentrations of Al2O3/water nanofluid were used as working fluids. The Reynolds number was varied from 1000 to 3500; and the heat flux was maintained as 45kW/m2. It was observed that the heat transfer performance of the DSM channel was higher than that of the SM channel.