Experimental Investigation Of Natural Circulation Loop Performance With Distilled Water And Aluminum Oxide Nanofluid
Abstract
The primary function of a Natural Circulation Loop (NCL) is to transport heat from a source to a sink. The main advantage of the natural circulation system is that the heat transport function is achieved without the aid of any pump. The absence of moving/rotating parts to generate the motive force for flow makes it less prone to failures reducing the maintenance and operating costs. The motive force for the flow is generated within the loop simply because of the presence of the heat source and the heat sink. A large variety of combinations of nanostructures and heat transfer fluids can be used to synthesize stable nanofluids with improved thermal transport properties. Nanostructures made from metals, oxides, carbides and carbon nanotubes can be dispersed into HTFs, such as water, ethylene glycol, hydrocarbons and fluorocarbons with or without the presence of stabilizing agents. In most experimental studies, nanofluids are synthesized in a two-step process, which are the first and the most classic synthesis method of nanofluids. In the present work nanoparticles of ZnO, CuO and Al2O3 were orchestrated. These integrated nanoparticles were then portrayed by utilizing different procedures like X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX).
The stabilization of loop fluid is achieved with the introduction of nanoparticles. The fluctuations in the velocity vs time curve would be decrease order and almost become linear with time. Also, the enhancement of flow rate in the loop may be record with the increase of temperature of heat source and also with the increase of volume fraction of Al2O3 in nanofluid. Ultrasonic velocity of a liquid is identified with the coupling powers between the iotas or the molecules. The accurate estimation of thickness, viscosity, ultrasonic velocity and subsequently the determined parameters, free volume and related parameters will give noteworthy data with respect to the state of affairs in an answer.
