Laminar Flow and Convective Heat Transfer of Water-Alumina Nanofluid Inside Horizontal Annuli with a Streamwise Moving Inner Cylinder

Nanofluids are nanometer sized engineered colloidal suspension of nanoparticles in base fluids. These fluids have unique transport properties and do not settle under gravity. These fluids have tremendous application in the field of heat transfer, extraction process, industrial cooling and microscale fluid applications. Pioneering nanofluids research in ANL has inspired many intellectual minds to unravel the tremendous potential of these fluids. Little is known about the nanoparticles and there is huge scope of theoretical understanding and experimental models. Recent researches have indicated that substitution of conventional coolants by nanofluids appears promising. Based on results available in the literatures, it has been found nanofluids have a much higher and strongly temperature-dependent thermal conductivity at very low particle concentrations

Heat transport and water flow are coupled by the movement of water vapour, which can account for significant transfer of latent energy of vaporization. Soil temperatures may be significantly underestimated when the movement of energy associated with vapour transport is not considered. For example, Cahill and Parlange (1998) reported that 40 to 60% of the heat flux in the top 2 cm of a bare field soil of Yolo silt loam was due to water vapour flow. Fourier?s law describing heat transport due to conduction (e.g., Campbell, 1985) thus needs to be extended to include heat transport by liquid water and water vapour flow. The general heat transport model then considers movement of soil heat by (i) conduction, (ii) convection of sensible heat by liquid

In an article called “Heat Transfer by conduction” by Mike Brown, it states “Thermal energy in the vibrating particles or molecules is passed on to nearby particles in a process called conduction”. This explains to us the process of conduction in which it relates to our design because when we insert the thermometer into the warm water, our goal is to keep the water warm with our cup so that once the thermometer makes DIRECT contact with the warm water, it will heat up the thermometer and give us an exact temperature.

Microfluidics has been studied over the past two decades. Since then several industries have adopted these technologies to improve their processes. This new technology helps to develop microstructures, where all chemical and physical parameters could be tested in a controlled environment at a much faster rate with fewer safety issues involved. The utility and the lifetime of microfluidic systems depend critically on their ability to maintain a flow without interruption. Indeed, clogging of channels due to adhesion of small particles to a wall has been recognized as a serious problem in many applications. Therefore, a large variety of academic and industrial research is going on these microfluidic devices, where particulate flow

Nanotechnology is the study of particles on the nanoscale with, at least one dimension being less than 100nm. (Chen, Schluesener, 2008) Nanoscale particles can come in many shapes and sizes, ranging from 100 - 1 nm. These particles can be found as rods, cones, spheres and many more complex matrices and patterns as seen in figure 1.(Champion, Katare, Mitragotri, 2007) Nanosilver will form a roughly spherical shape as can be seen in figure 2. (Utopia Silver Supplements, 2012)

The field of Nanotechnology involves the manipulation of infinitesimally small matter. The National Nanotechnology Initiative defines nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers. By employing nanotechnology and its opportunity for miniaturisation in the development of consumer products, we have placed ourselves on a paradigm changing technology path permitting considerable efficiency savings in terms of cost, energy and resources. These developments would surely have not been possible without the avail of nanotechnological processes. Accordingly, the field of nanotechnology is a rapidly expanding and major innovative force amongst the scientific community, and the increasing

“Capturing the fundamental growth and evolution of these particles in motion will help us immensely in our work with synthetic materials and their interactions with biological systems,” says Gianneschi, who serves as the Jacob and Rosaline Cohn Professor of Chemistry in the Weinberg College of Arts and Sciences. Neither he nor Parent has likely underestimated the significance of this study in light of the prospective influence it may very well have on future research. In fact, new insightful studies can now be published simply based on recordings of feats already accomplished with nanoparticles because the value will be not in the feat itself but, rather, in the well-defined recording thereof. Much like the value in Gianneschi’s study, it would be in learning more about the dynamics and behavioral parameters of nanoparticles.

Since the Bi value of the aluminum system is less than 0.1, convection from the water to the surface of the cylinder is the rate limiting heat transfer mechanism. Thus, a lumped-parameter analysis can be safely applied. The Plexiglas system, on the other hand, has a Bi >> 0.1, and the rate limiting mechanism is conduction in the cylinder.

thermal system fulfil the requirements (Bi < 0.1) in order to be considered as a lumped

There are certain assumptions that will be made to carry out the said experiment. The heat flow will always be considered one dimensional. The system is considered

Inhomogeneous liquid bound in nanopores is of impressive significance in different modern procedures and logical fields for example, adsorption, polymers, grease and tribology. The properties of liquid bound in nanopores or nanochannels are not quite the same as those in the mass stage because of divider particle communications and divider geometry. A ton of research has been routed to speak to the inhomogeneous conduct of restricted liquids from exploratory estimations, atom reproductions to hypothetical models, and the established thickness practical hypothesis (DFT) has been ended up being effective in clarifying and foreseeing the conduct of inhomogeneous liquids DFT is a helpful tool for speaking to the conduct of limited liquids

This work aims to investigate the heat transfer and pressure drop characteristics of carbon nanotube water-based nano-fluids as a working fluid inside the double pipe heat exchanger. Diameters of inner and outer copper tubes (ID and OD) were 6.35 and 12.7mm respectively (in accordance with ANSI/ASME/API 5L). Nano-fluids were prepared using two-step method at mass concentrations of 0.1%-0.3% by dispersing the multi-walled carbon nanotubes, (CNTs) into the deionized water. Since this work can be technically important, therefore, thermal conductivity of nano-fluids were experimentally measured using KD2 Decagon instruments at different mass concentrations and temperatures. In order to assess the thermal performance of nano-fluids, forced convection experiments were conducted at laminar and turbulent flow regimes (90095%

Keywords: Boron nitride; nanofillers; finite element; density functional theory; molecular dynamics; Tersoff potential; hybrid nanostructures

An alternative is to use air as the cooling medium but their performance drops in hot weather conditions. Maximization of overall efficiency is as vital as the cost and availability of water. Therefore there is a need to integrate the technologies of air cooled and water cooled condensers. This paper will focus on parallel condensing where steam from the turbine is ducted in parallel to both air cooled and water cooled condensers. To optimize the parallel condensing capacities of air cooled and water cooled condensers considering parameters such as ambient temperature, pressure, availability of water, fan power, pumping costs.

Nanoparticle’s surface energy also increases as the size reduces (Guozhong, 2005). There is a strong tendency for a particle to minimize this thermodynamic unfavourable energy making dangling bonds (Henry , 2008).Therefore, the reactivity of a nanoparticle increases drastically as its size reaches a few nm (Agrawal , 2013)