Experimental and Theoretical Studies of Thermophysical Properties of MgO-Water Nanofluid

2020 ◽  
Vol 1008 ◽  
pp. 47-52
Author(s):  
Abdallah Yousef Mohammed Ali ◽  
Ahmed Hassan El-Shazly ◽  
Marwa Farouk El-Kady ◽  
Hesham Ibrahim Elqady ◽  
Kholoud Madih ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermophysical Properties ◽  
Volume Fraction ◽  
Sol Gel ◽  
Solid Volume Fraction ◽  
Ammonium Bromide ◽  
Distilled Water ◽  
Step Method ◽  
Mgo Nanoparticles ◽  
Cetyl Trimethyl Ammonium

Magnesium oxide (MgO) nanoparticles were synthesized using the sol-gel technique then characterized. Cetyl Trimethyl Ammonium Bromide (CTAB) surfactant was added to reduce Van der Waal forces among MgO nanoparticles and distilled water forming a stable nanofluid using two-step method with aid of ultrasound sonication. Pure distilled water and nanofluids with different volume fractions of 0.25, 0.5, 0.75, and 1% are used as working fluids. Thermophysical properties of prepared nanofluids were measured experimentally and determined theoretically. Effect of solid volume fraction on the thermophysical properties; including thermal conductivity, heat capacity, viscosity, and density of MgO-water nanofluids are discussed. Moreover, experimental results have been compared with the suitable correlations for MgO-water nanofluid. The findings show that thermal conductivity, viscosity, and density of nanofluid increases with increasing solid volume fraction.

Experimental Evaluation in Thermal Conductivity Enhancement and Heat Transfer Optimization of Eco-Friendly Al2O3–Pure Coconut Oil Based Nano Fluids

2020 ◽  
Vol 13 (3) ◽  
Author(s):  
S. V. Sujith ◽  
Anand Kumar Solanki ◽  
Rahul S. Mulik
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Thermophysical Properties ◽  
Experimental Evaluation ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Coconut Oil ◽  
Conductivity Enhancement ◽  
Almost All ◽  
Nano Fluids

Abstract The present study reports an experimental evaluation of thermal conductivity of Al2O3/pure coconut oil nano fluids with solid volume fraction varying from 0.1% to 1.2% at a temperature ranging from 303 K to 413 K, respectively. Additionally, the thermophysical properties such as thermal diffusivity, density, and specific heat were also measured. The effect of solid volume fraction and temperature on thermophysical properties of nano fluids was examined. The results confirmed that the thermal conductivity of nano fluids was higher than that of the base fluid with an increase in the solid volume fraction and temperature. Apart from this, the efficiency of nano fluids for the heat transfer application has been evaluated for optimization based on different figures of merit. Further, the experimental thermal conductivity data were compared with different existing models and correlations as the thermal conductivity enhancement of the nano fluid is directly or indirectly a function of almost all thermophysical properties. Hence, a novel dimensionless correlation was developed for predicting the thermal conductivity of pure coconut oil/Al2O3 nano fluids in terms of almost all the thermophysical parameters calculated from the experimental data.

scholarly journals SYNTHESIS OF COPPER NANOPARTICLES USING ASCORBIC ACID AND CETYL TRIMETHYL AMMONIUM BROMIDE

2018 ◽  
Vol 11 (14) ◽  
pp. 62
Author(s):  
Saurabh Singh ◽  
Bimlesh Kumar ◽  
Narendra Kumar Pandey ◽  
Barinder Kaur ◽  
Arun Kumar ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Copper Nanoparticles ◽  
Cetyl Trimethyl Ammonium Bromide ◽  
Ammonium Bromide ◽  
Distilled Water ◽  
Bromide Solution ◽  
Cetyl Trimethyl Ammonium ◽  
Dialysis Bag ◽  
Spray Dried ◽  
Glass Beaker

Objective: The present study highlights the development of a method to synthesize copper nanoparticles (CuNPs).Methods: CuNPs were developed using 0.01 M copper penta sulfate and 0.11 M of ascorbic acid (AA) and 0.03 M of cetyl trimethyl ammonium bromide solution. The synthesized CuNPs were differentiated through filtration and washed by water (deionized). CuNPs were kept in dialysis bag 70 KD in a 250 mL glass beaker along with distilled water. The assembly was kept on a magnetic stirrer for 24 h at 500 rpm. Then, the dialysis bag containing CuNPs solution was filtered by a filter assembly with 0.2 μm nylon filter. The filtered CuNPs were spray dried with the help of spray drier.Results: The prepared CuNPs were found to be 440 nm with zeta potential of −10 mV and polydispersity index 0.314.Conclusion: The investigation deciphers the promising and material technique to synthesis of CuNPs by methods for synthetic reduction utilizing strategy using AA (0.2 M) and sodium hydroxide (1 M), and Syloid 244FP.

Evaluation of Surfactants on Thermo-Physical Properties of Magnesia-Oil Nanofluid

2018 ◽  
Vol 928 ◽  
pp. 106-112 ◽  
Author(s):  
Abdallah Yousef Mohammed Ali ◽  
Ahmed H. El-Shazly ◽  
M.F. Elkady ◽  
S.E. AbdElhafez
Keyword(s):  
Vinyl Pyrrolidone ◽  
Poly Vinyl Alcohol ◽  
Ammonium Bromide ◽  
X Ray Diffraction ◽  
Mgo Nanoparticles ◽  
Transmission Electron ◽  
Wet Chemical ◽  
Cetyl Trimethyl Ammonium ◽  
Poly Vinyl Pyrrolidone ◽  
The Impact

The prime purpose of the current study was to investigate the consequence of surfactant on the kinematic viscosity, thermal conductivity, and stability of MgO-oil based nanofluid. Magnesia (MgO) nanoparticles were prepared by the wet chemical method. Structural and morphological analysis of synthesized nanoparticles were performed via X-ray diffraction (XRD) and Transmission electron microscope (TEM). Subsequently, nanofluid was prepared at a solid concentration of 0.025% in presence of various surfactants with the aid of ultrasonic technique. The impact of the different surfactants (Cetyl Trimethyl Ammonium Bromide (CTAB), Poly Vinyl Pyrrolidone (PVP), Poly Vinyl Alcohol (PVA), and Oleic Acid) on the nanofluid stability was tested. It was evident that CTAB and PVA surfactants establish the most stable prepared MgO-oil based nanofluid. The experiments revealed that the maximum UV–Vis absorbance of the solution corresponds to the dispersion of CTAB in the base fluid.

scholarly journals Synthesis of hybrid nanofluid with two-step method

2018 ◽  
Vol 67 ◽  
pp. 03057 ◽  
Author(s):  
Wayan Nata Septiadi ◽  
Ida Ayu Nyoman Titin Trisnadewi ◽  
Nandy Putra ◽  
Iwan Setyawan
Keyword(s):  
Thermal Conductivity ◽  
Base Fluid ◽  
Volume Fraction ◽  
Heat Transfer Fluid ◽  
Hybrid Nanofluid ◽  
Test Results ◽  
Step Method ◽  
Fluid Mixture ◽  
High Level ◽  
Better Than

Nanofluid is a liquid fluid mixture with a nanometer-sized solid particle potentially applied as a heat transfer fluid because it is capable of producing a thermal conductivity better than a base fluid. However, nanofluids have a weakness that is a high level of agglomeration as the resulting conductivity increases. Therefore, in this study, the synthesis of two nanoparticles into the base fluid called hybrid nanofluids. This study aims to determine the effect of nanoparticle composition on the highest thermal conductivity value with the lowest agglomeration value. This research was conducted by dispersing Al2O3-TiO2 nanoparticles in water with volume fraction of 0.1%, 0.3%, 0.5%, 0.7% in the composition of Al2O3-TiO2 ratio of 75%:25%, 50%:50%, 25%:75%. The synthesis was performed with a magnetic stirrer for 30 minutes. The tests were carried out in three types: thermal conductivity testing with KD2, visual agglomeration observation and absorbance measurements using UV-Vis, wettability testing with HSVC tools and Image applications. The test results showed that the ratio composition ratio of 75% Al2O3-25% TiO2 with a volume fraction of 0.7% resulted in an increase in optimum thermal conductivity with the best wettability and the longest agglomeration level.

Experimental Measurement of Thermophysical Properties of Alumina- MWCNTs/Salt–Water Hybrid Nanofluids

2020 ◽  
Vol 16 (5) ◽  
pp. 734-747 ◽  
Author(s):  
Amir Hossein Sharifi ◽  
Iman Zahmatkesh ◽  
Fatemeh F. Bamoharram ◽  
Amir Hossein Shokouhi Tabrizi ◽  
Safieh Fazel Razavi ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Salt Concentration ◽  
Thermophysical Properties ◽  
Base Fluid ◽  
Volume Fraction ◽  
Ph Value ◽  
Nanoparticle Volume Fraction ◽  
Optimal Conditions ◽  
Hybrid Nanofluids

Background: Hybrid nanofluids are considered as an extension of conventional nanofluids which are prepared through suspending two or more nanoparticles in the base fluids. Previous studies on hybrid nanofluids have measured their thermal conductivity overlooking other thermophysical properties such as viscosity and electrical conductivity. Objective: An experimental investigation is undertaken to measure thermal conductivity, viscosity, and electrical conductivity of a hybrid nanofluid prepared through dispersing alumina nanoparticles and multiwall carbon nanotubes in saltwater. These properties are the main important factors that must be assessed before performance analysis for industrial applications. Methods: The experimental data were collected for different values of the nanoparticle volume fraction, temperature, salt concentration, and pH value. Attention was paid to explore the consequences of these parameters on the nanofluid’s properties and to find optimal conditions to achieve the highest value of the thermal conductivity and the lowest values of the electrical conductivity and the viscosity. Results: The results demonstrate that although the impacts of the pH value and the nanoparticle volume fraction on the nanofluid’s thermophysical properties are not monotonic, optimal conditions for each of the properties are reachable. It is found that the inclusion of the salt in the base fluid may not change the thermal conductivity noticeably. However, a considerable reduction in the viscosity and substantial elevation in the electrical conductivity occur with an increase in the salt concentration. Conclusion: With the addition of salt to a base fluid, the thermophysical properties of a nanofluid can be controlled.

Experimental Investigation for the Thermo-physical Properties and Stability of CeO2, ZrO2, and Al2O3 Mixed with Ethylene Glycol and Distilled Water

2019 ◽  
Vol 70 (11) ◽  
pp. 3908-3912
Author(s):  
Altayyeb Alfaryjat ◽  
Mariana Florentina Stefanescu ◽  
Alexandru Dobrovicescu
Keyword(s):  
Thermal Conductivity ◽  
Experimental Investigation ◽  
Ethylene Glycol ◽  
Physical Properties ◽  
Visual Observation ◽  
Distilled Water ◽  
Step Method ◽  
Nanoparticles Concentration ◽  
Thermo Physical Properties

In this work, the effects of nanoparticles concentration on the density, thermal conductivity, and viscosity of Al2O3, CeO2 and ZrO2 suspended in 20% of ethylene glycol (EG) and 80% of distilled water (DW) is experimentally investigated. By using two step method, the nanofluid samples are provided at different concentrations, including 0.5%, 1% and 2 %. Visual observation of the nanofluid samples showed that CeO2-EG/DW and ZrO2-EG/DW have higher stability for one week more that Al2O3-EG/DW. The results indicate that the density, viscosity and thermal conductivity of the nanofluids increased with increasing the nanoparticles concentration. The highest enhancement of the thermal conductivity was found to be 9.6% for 2% concentration of CeO2-EG/DW at 25�C. Al2O3-EG/DW shows the lowest density and viscosity between all types of the nanofluids.

Thermal Conductivity Analysis of Ethylene Glycol/H2O- Based MgFe2O4 Ferrofluid

2022 ◽  
Vol 1048 ◽  
pp. 83-88
Author(s):  
K. Ajith ◽  
Archana Sumohan Pillai ◽  
I.V. Muthu Vijayan Enoch ◽  
A. Brusly Solomon
Keyword(s):  
Thermal Conductivity ◽  
Magnetic Flux ◽  
Surface Morphology ◽  
Ethylene Glycol ◽  
Structural Characterization ◽  
Magnetic Nanoparticle ◽  
Volume Fraction ◽  
Current Investigation ◽  
Step Method ◽  
Volume Fractions

The current investigation aims to synthesize MgFe2O4 magnetic nanoparticle and measure the thermal conductivity of MgFe2O4 ferrofluid. Prepared MgFe2O4 nanoparticle's structural characterization, the concentration of constituents, and surface morphology were analyzed using XRD, EDAX, and TEM respectively. This study also analyses the influence of magnetic flux on the thermal conductivity of MgFe2O4/ EG: H2O (60:40) based ferrofluids formed by the two-step method. Thermal conductivity of ferrofluid measured at different volume fractions (ranging from 0.01% to 0.20%) show that thermal conductivity augmented with an escalation in volume fraction and the highest enhancement of 10.32% was reached at 0.20% volume fraction. Results indicate that the applied magnetic flux improves the thermal conductivity of ferrofluid from 10.32% to 14.75% at 0.20% volume fraction and 350 Gauss Magnetic flux.

Enhancement of Heat Transfer Characteristics in an Absorber Tube of a Solar-Based Energy System Using Nanofluids

2015 ◽  
Author(s):  
Adnan Alashkar ◽  
Mohamed Gadalla
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Thermophysical Properties ◽  
Volume Fraction ◽  
Effective Density ◽  
Heat Transfer Characteristics ◽  
Overall Heat Transfer Coefficient ◽  
Transfer Characteristics

In this present paper, nanoparticles are dispersed into a base fluid, their effect on the thermophysical properties and overall heat transfer coefficient of the fluid inside a circular tube representing an absorber tube of a Parabolic Trough Solar Collector (PTSC) is studied. Different models are used to predict the effective density, specific heat capacity, viscosity and thermal conductivity of the nanofluids. For the analytical analysis, Alumina (Al2O3), Copper (Cu) and Single Wall Carbon Nanotubes (SWCNT) nanoparticles are dispersed into Therminol VP-1 oil. The resulting nanofluids are compared in terms of their thermophysical properties, their convective heat transfer characteristics and their overall heat transfer coefficient. Moreover, the effect on increasing the volume fraction on the properties and the heat transfer coefficient is studied. The computational analysis results show that the thermal conductivity increases with the increase of the volume fraction. In addition Therminol/SWCNT showed the highest thermal conductivity enhancement of 98% for a volume fraction of 3%. Further, the overall heat transfer coefficient increases with the increase of volume fraction, and Therminol/SWCNT showed the highest enhancement with 72% compared to Al2O3/Therminol and Cu/Therminol that showed an enhancement of 29% and 43% respectively.

scholarly journals Urea-Assisted Synthesis of Mesoporous TiO2 Photocatalysts for the Efficient Removal of Clofibric Acid from Water

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6035
Author(s):  
Lidia Favier ◽  
Amalia Maria Sescu ◽  
Elaziouti Abdelkader ◽  
Laurence Oughebbi Berthou ◽  
Doina Lutic
Keyword(s):  
Sol Gel ◽  
Mesoporous Tio2 ◽  
Clofibric Acid ◽  
Water Remediation ◽  
Ammonium Bromide ◽  
Tio2 Photocatalysts ◽  
Different Temperatures ◽  
Cetyl Trimethyl Ammonium ◽  
Catalyst Reusability ◽  
High Yields

Mesoporous TiO2 photocatalysts intended for the advanced removal of clofibric acid (CA) from water were synthesized by the sol-gel method in a medium containing cetyl-trimethyl-ammonium bromide (CTAB) and urea, using either ethanol or isopropanol to dilute the TiO2 precursor. The activation of the samples was undertaken at 550, 650 and 750 °C. The XRD revealed that the nature of the solvent resulted in significant differences in the anatase-to-rutile ratios obtained at different temperatures. The specific surface area values were situated between 9 and 43 m2g−1 and the band gap values were similar for all the samples. The photocatalytic activity of the prepared samples was examined for the degradation of CA, an emergent water contaminant. The photocatalytic tests performed under UV-A irradiation revealed that the photo-reactivity of these materials depends on the calcination temperature. The best results were obtained for the samples calcined at 750 °C, which showed high yields of CA elimination, as well as almost complete mineralization (over 95%) after 180 min of reaction. Good results in terms of catalyst reusability in the reaction were found for the catalyst showing the highest photo-reactivity. Therefore, the samples can be considered good candidates for future water remediation applications.

Sign in / Sign up

Export Citation Format

Share Document