scholarly journals AL2O3 Nanofluids as Heat Transfer Liquids in Automotives

Author(s):  
M. YASASWI ◽  
R.V. PRASAD ◽  
T.JAYANDA KUMAR

The thermal conductivity of heating or cooling fluids is a very important property in the development of energy efficient heat transfer systems, which is one of the important needs of many industries. However, low thermal conductivity is a primary limitation in developing energy-efficient heat transfer fluids that are required for cooling purposes. Nanofluids are nanotechnology-based heat transfer fluids that are engineered by stably dispersing nanometer-sized (below 100nm) solid particles (such as ceramics, metals, alloys, semiconductors, nanotubes, and composite particles) in conventional heat transfer fluids (such as water, oil, diesel, ethylene glycol and mixtures) at relatively low particle volume concentrations. These suspended nanoparticles can change the transport and thermal properties of the base fluid. Adding to ethylene glycol, it has been observed that an enhancement of nearly 36 % with al2o3 nanoparticles and 40% enhancement with copper nanoparticles in the thermal conductivity. This paper focuses on some of the automotive applications such as coolant for automobiles, showcases a few of them that are believed to have the highest probability of success in this highly competitive industry and to raise the awareness on the promise of nanotechnology, its potential impact on the future of the automotive industry.

2014 ◽  
Vol 66 (2) ◽  
pp. 238-243 ◽  
Author(s):  
Ayush Jain ◽  
Imbesat Hassan Rizvi ◽  
Subrata Kumar Ghosh ◽  
P.S. Mukherjee

Purpose – Nanofluids exhibit enhanced heat transfer characteristics and are expected to be the future heat transfer fluids particularly the lubricants and transmission fluids used in heavy machinery. For studying the heat transfer behaviour of the nanofluids, precise values of their thermal conductivity are required. For predicting the correct value of thermal conductivity of a nanofluid, mathematical models are necessary. In this paper, the effective thermal conductivity of various nanofluids has been reported by using both experimental and mathematical modelling. The paper aims to discuss these issues. Design/methodology/approach – Hamilton and Crosser equation was used for predicting the thermal conductivities of nanofluids, and the obtained values were compared with the experimental findings. Nanofluid studied in this paper are Al2O3 in base fluid water, Al2O3 in base fluid ethylene glycol, CuO in base fluid water, CuO in base fluid ethylene glycol, TiO2 in base fluid ethylene glycol. In addition, studies have been made on nanofluids with CuO and Al2O3 in base fluid SAE 30 particularly for heavy machinery applications. Findings – The study shows that increase in thermal conductivity of the nanofluid with particle concentration is in good agreement with that predicted by Hamilton and Crosser at typical lower concentrations. Research limitations/implications – It has been observed that deviation between experimental and theoretical results increases as the volume concentration of nanoparticles increases. Therefore, the mathematical model cannot be used for predicting thermal conductivity at high concentration values. Originality/value – Studies on nanoparticles with a standard mineral oil as base fluid have not been considered extensively as per the previous literatures available.


2008 ◽  
Vol 12 (2) ◽  
pp. 27-37 ◽  
Author(s):  
Vasu Velagapudi ◽  
Krishna Konijeti ◽  
Kumar Aduru

Nanofluids exhibits larger thermal conductivity due to the presence of suspended nanosized solid particles in them such as Al2O3, Cu, CuO,TiO2, etc. Varieties of models have been proposed by several authors to explain the heat transfer enhancement of fluids such as water, ethylene glycol, engine oil containing these particles. This paper presents a systematic literature survey to exploit the thermophysical characteristics of nanofluids. Based on the experimental data available in the literature empirical correlation to predict the thermal conductivity of Al2O3, Cu, CuO, and TiO2 nanoparticles with water and ethylene glycol as base fluid is developed and presented. Similarly the correlations to predict the Nusselt number under laminar and turbulent flow conditions is also developed and presented. These correlations are useful to predict the heat transfer ability of nanofluids and takes care of variations in volume fraction, nanoparticle size and fluid temperature. The improved thermophysical characteristics of a nanofluid make it excellently suitable for future heat exchange applications. .


Author(s):  
Bao Yang ◽  
Zenghu Han

Thermal management in the next decade of microelectronics and optoelectronics will require heat transfer fluids with improved performance over those currently available. The strategy of adding SOLID particles to fluids for improving thermal conductivity has been pursued for nearly a century. In this work, a novel concept of using LIQUID nanodroplets for enhancing thermal conductivity has been developed and was experimentally-demonstrated in water-in-FC72 suspensions, called "nanoemulsion-fluids". The thermal conductivity of FC72 is found to be increased by up to 52% for a nanoemulsion-fluid containing 12vol% water nanodroplets of radius 9.8nm. Such types of nanoemulsion-fluids possess long-term stability and can be mass produced because of no needs for SOLID nanoparticles. The development of nanoemulsion-fluids would open a new direction for thermal fluids studies.


2017 ◽  
Vol 1143 ◽  
pp. 207-213
Author(s):  
Madalina Georgiana Moldoveanu ◽  
Tudor Mihai Simionescu ◽  
Alina Adriana Minea ◽  
Adrian Dima

Over the past years, the development of functional heat transfer fluids by compounding different substances or different phases of matter (solid, liquid, or gas) has raised increasing interest in view of their potential applications in technologies. In particular, the nanofluids in which the solid particles (<100 nm or smaller) are incorporated as the dispersed phase in the suspensions, are currently focus of great attention because of their perspective potentials as high-performance heat transfer fluids. The potential advantage of utilizing the nanofluid lies mainly in its drastic increase in the thermal conductivity. This paper presents a study of the thermophysical characteristics of some nanofluids and their hybrids. General correlations for the effective thermal conductivity and viscosity of nanofluids are used for this analysis. Regarding the importance of thermophysical properties of water based drilling fluids, the effects of insertion of two oxides in an alumina-water nanofluid on the thermal conductivity, viscosity and density of distilled water were investigated. According to the results, viscosity and density of the nanofluids increased with the concentration. At high concentrations, the least increase in the viscosity of distilled water by adding the nanomaterials is related to H2 (8.2% increase at 1.0 wt.%). As the results show, increase in the density of distilled water by adding the nanomaterials is insignificant, that in the worst case it did not exceed 0.9%. The least increase in the density of base fluid at high concentrations was for H1.


1996 ◽  
Vol 457 ◽  
Author(s):  
J. A. Eastman ◽  
U. S. Choi ◽  
S. Li ◽  
L. J. Thompson ◽  
S. Lee

ABSTRACTLow thermal conductivity is a primary limitation in the development of energy-efficient heat transfer fluids required in many industrial applications. To overcome this limitation, a new class of heat transfer fluids is being developed by suspending nanocry stalline particles in liquids such as water or oil. The resulting “nanofluids” possess extremely high thermal conductivities compared to the liquids without dispersed nanocrystalline particles. For example, 5 volume % of nanocrystalline copper oxide particles suspended in water results in an improvement in thermal conductivity of almost 60% compared to water without nanoparticles. Excellent suspension properties are also observed, with no significant settling of nanocrystalline oxide particles occurring in stationary fluids over time periods longer than several days. Direct evaporation of Cu nano-particles into pump oil results in similar improvements in thermal conductivity compared to oxide-in-water systems, but importantly, requires far smaller concentrations of dispersed nanocrystalline powder.


2011 ◽  
Vol 133 (11) ◽  
Author(s):  
K. Hari Krishna ◽  
Harish Ganapathy ◽  
G. Sateesh ◽  
Sarit K. Das

Nanofluids, solid-liquid suspensions with solid particles of size of the order of few nanometers, have created interest in many researchers because of their enhancement in thermal conductivity and convective heat transfer characteristics. Many studies have been done on the pool boiling characteristics of nanofluids, most of which have been with nanofluids containing oxide nanoparticles owing to the ease in their preparation. Deterioration in boiling heat transfer was observed in some studies. Metallic nanofluids having metal nanoparticles, which are known for their good heat transfer characteristics in bulk regime, reported drastic enhancement in thermal conductivity. The present paper investigates into the pool boiling characteristics of metallic nanofluids, in particular of Cu-H2O nanofluids, on flat copper heater surface. The results indicate that at comparatively low heat fluxes, there is deterioration in boiling heat transfer with very low particle volume fraction of 0.01%, and it increases with volume fraction and shows enhancement with 0.1%. However, the behavior is the other way around at high heat fluxes. The enhancement at low heat fluxes is due to the fact that the effect of formation of thin sorption layer of nanoparticles on heater surface, which causes deterioration by trapping the nucleation sites, is overshadowed by the increase in microlayer evaporation, which is due to enhancement in thermal conductivity. Same trend has been observed with variation in the surface roughness of the heater as well.


2007 ◽  
Vol 455 (1-2) ◽  
pp. 66-69 ◽  
Author(s):  
Dae-Hwang Yoo ◽  
K.S. Hong ◽  
Ho-Soon Yang

Mathematics ◽  
2021 ◽  
Vol 9 (24) ◽  
pp. 3153
Author(s):  
Nidal H. Abu-Hamdeh ◽  
Abdulmalik A. Aljinaidi ◽  
Mohamed A. Eltaher ◽  
Khalid H. Almitani ◽  
Khaled A. Alnefaie ◽  
...  

The current article presents the entropy formation and heat transfer of the steady Prandtl-Eyring nanofluids (P-ENF). Heat transfer and flow of P-ENF are analyzed when nanofluid is passed to the hot and slippery surface. The study also investigates the effects of radiative heat flux, variable thermal conductivity, the material’s porosity, and the morphologies of nano-solid particles. Flow equations are defined utilizing partial differential equations (PDEs). Necessary transformations are employed to convert the formulae into ordinary differential equations. The implicit finite difference method (I-FDM) is used to find approximate solutions to ordinary differential equations. Two types of nano-solid particles, aluminium oxide (Al2O3) and copper (Cu), are examined using engine oil (EO) as working fluid. Graphical plots are used to depict the crucial outcomes regarding drag force, entropy measurement, temperature, Nusselt number, and flow. According to the study, there is a solid and aggressive increase in the heat transfer rate of P-ENF Cu-EO than Al2O3-EO. An increment in the size of nanoparticles resulted in enhancing the entropy of the model. The Prandtl-Eyring parameter and modified radiative flow show the same impact on the radiative field.


Author(s):  
Anwar Ilmar RAMADHAN ◽  
Wan Hamzah AZMI ◽  
Rizalman MAMAT

In recent years, research has focused on enhancing the thermo-physical properties of a single component nanofluid. Therefore, hybrid or composite nanofluids have been developed to improve heat transfer performance. The thermo-physical properties of the Al2O3-TiO2-SiO2 nanoparticles suspended in a base of water (W) and ethylene glycol (EG) at constant volume ratio of 60:40 and different volume concentrations were investigated. The experiment was conducted for the volume concentrations of 0.05, 0.1, 0.2, and 0.3% of Al2O3-TiO2-SiO2 nanofluids at different temperatures of 30, 40, 50, 60, and 70 °C. Thermal conductivity and dynamic viscosity measurements were carried out at temperatures ranging from 30 to 70 °C by using KD2 Pro Thermal Properties Analyzer and Brookfield LVDV III Ultra Rheometer, respectively. The highest thermal conductivity for tri-hybrid nanofluids was obtained at 0.3% volume concentration, and the maximum enhancement was increased up to 9% higher than the base fluid (EG/W). Tri-hybrid nanofluids with a volume concentration of 0.05% gave the lowest effective thermal conductivity of 4.8 % at 70 °C temperature. Meanwhile, the dynamic viscosity of the tri-hybrid nanofluids was influenced by volume concentration and temperature. Furthermore, tri-hybrid nanofluids behaved as a Newtonian fluid for volume concentrations from 0.05 to 3.0%. The properties enhancement ratio (PER) estimated that the tri-hybrid nanofluids will aid in heat transfer for all samples in the present. The new correlations for thermal conductivity and dynamic viscosity of tri-hybrid nanofluids were developed with minimum deviation. As a conclusion, the combination of the enhancement in thermal conductivity and dynamic viscosity for tri-hybrid at 0.3% volume concentration was found the optimum condition with more advantage for heat transfer than other concentrations.


Sign in / Sign up

Export Citation Format

Share Document