scholarly journals Thermo-Acoustical and FTIR Spectroscopic Research of Nanofluids at Different Temperatures

2020 ◽  
Vol 8 (5) ◽  
pp. 5306-5309
Keyword(s):  
Thermal Conductivity ◽  
Bond Formation ◽  
Nano Particles ◽  
Wide Spread ◽  
Nano Fluid ◽  
Cohesive Properties ◽  
Physical Chemical ◽  
Different Temperatures ◽  
Chemical Studies ◽  
Nano Fluids

In recent years the greater interest of increase in thermal conductivity have attracted because there is comparison to that of the base fluids by Nano fluids. The wide spread of nano particles of the formation nano fluid of a base fluid, takes place. These nano fluids are very much useful in thermo dynamical applications and in the study of so many physical-chemical studies. The properties of molecular of sound in nano fluids like transmission undergo changes of associated systems in highly dependent and the cohesive properties of liquids. Generally nano fluid is having high thermal conductivity values. Four different temperatures have been studied in this thermo-acoustical work and FTIR Spectrum of Coo Nano fluid at T (303.15, 308.15, 313.15 and 318.15) K. The observed results are explained in the nature of interactions and bond formation.

scholarly journals Thermophysical Properties of Hybrid Nano Fluids

2019 ◽  
Vol 9 (1) ◽  
pp. 5038-5040
Keyword(s):  
Thermophysical Properties ◽  
Acid Treatment ◽  
Nano Particles ◽  
Agriculture Waste ◽  
Nano Fluid ◽  
Bamboo Leaves ◽  
Pure Sio2 ◽  
Nano Fluids

In this study, the ash from agriculture waste of bamboo leaves was used in the synthesis of silica nano particles followed by leaching and acid treatment. The required ash from agriculture waste (bamboo leaves) is subjected to sintered at 700 degree centigrade for 5 hours to eliminate residues from ash. The obtained powder was treated with 1M NaOH for leaching and then acid- treatment with 0.5 M H2SO4 to precipitate pure SiO2 nano particles powder. The synthesized silica were characterized by XRD, FTIR, SEM, PSA, ZETA POTENSIAL. And the synthesis of CuO-SiO2 hybrid nano fluid from the agriculture waste of silica.

scholarly journals Performance of Heat Transfer and Friction Factor of Heat Exchanger with Al2o3/ Water Nano Fluids

2019 ◽  
Vol 9 (1) ◽  
pp. 2723-2726
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Heat Transfer Enhancement ◽  
Flow Characteristics ◽  
Plain Water ◽  
Twisted Tape ◽  
Transfer Enhancement ◽  
Nano Fluid ◽  
Fluids Mechanics ◽  
Nano Fluids

This paper summary of heat transfer characteristics and nano fluids mechanics by using single phase convection techniques. Gas having less thermal conductivity compare than the liquids having high thermal conductivity. The heat transfer enhancement improved by using nano fluids Al2O3 compared with base water. The heat transfer enhancement was analysed with plain tube and twisted tape inserts with nano fluids. The experimental investigation was analysed and reading was taken to improve the heat transfer and friction flow characteristics. The Reynolds number varies from different ranges with plain water and Nano fluids. The experimental record of nano fluid heat transfer value was increased with 2.89 percentage compare with the experimental record of plain water. The nano fluids has more concentration than the plain water.

The Thermal Conductivity and Viscosity of Non-Polar Hybrid CuO Nanofluid (CuO+ DEA + Cyclohexane) (CuO + DEA + 1-4 Dioxane)

2019 ◽  
Vol 17 (12) ◽  
pp. 965-967
Author(s):  
B. Rohini ◽  
A. Kingson Solomon Jeevaraj
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Copper Oxide ◽  
Viscosity Measurement ◽  
Nano Particles ◽  
Conductivity Measurements ◽  
Transfer Enhancement ◽  
Binary Fluid ◽  
New Class ◽  
Nano Fluid

Nano fluid is the new class of engineering fluid for the heat transfer applications. Copper Oxide (CuO) nano particles were dispersed in the binary fluid (Cyclohexane + DEA) and (1-4 dioxane + DEA) then prepared non-polar hybrid CuO nano fluid. Thermal conductivity (K ) and viscosity (η) of non-polar hybrid CuO nanofluid measured for very low concentration from 0.01 M to 0.06 M and various temperatures ranging from 298 K to 318 K. The transient hotwire method is used for the thermal conductivity measurements and viscometer is used for the viscosity measurement. As the concentration increases K decreases but it increases with the increase of temperature. η increases with the increase of concentration as well as with temperature. From the results the spectacular heat transfer enhancement occurred in the hybrid CuO nanofluid compared to the binary mixtures. The percentage increment of thermal conductivity of non-polar hybrid CuO nano fluid is of 15% to 20% and the viscosity increment is of from 18% to 25%.

Thermal Conductivity Augmentation in Polymeric Nanocomposites

2011 ◽  
Author(s):  
D. C. Moreira ◽  
L. A. Sphaier ◽  
L. C. S. Nunes ◽  
J. M. L. Reis
Keyword(s):  
Thermal Conductivity ◽  
Composite System ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Nano Particles ◽  
Alumina Nanoparticles ◽  
Polymeric Nanocomposites ◽  
Nanocomposite System ◽  
Alumina Particles ◽  
Different Temperatures

This paper presents an experimental analysis of the thermal conductivity of a nanocomposite system composed of a unsaturated polyester resin as matrix and alumina nanoparticles as filler. The nano particles used are 30–40 nanometers gamma alumina particles. Samples are fabricated using simple molding and no specialized homogenization equipment is used for mixing the particles with the liquid resin. The thermal conductivity is measured using the Fox-50 device, manufactured by LaserComp. Measurements are taken at different temperatures (from 0° to 50°C) for different batches of samples varying the fraction of nanoparticles used in the composite system. Finally, the thermal conductivity measurements are compared with models for predicting the thermal conductivity of composite materials with nanoparticles, showing that the obtained results are over the values estimated by these models.

Impact of nano-particles shapes on Al2O3-water nano-fluid flow due to a stretching cylinder

2019 ◽  
Vol 30 (5) ◽  
pp. 2809-2832 ◽  
Author(s):  
Sajjad Haider ◽  
Adnan Saeed Butt ◽  
Imran Syed Muhammad ◽  
Asif Ali ◽  
Yun-Zhang Li ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Nano Particles ◽  
Stretching Cylinder ◽  
Nano Particle ◽  
Heat Transmission ◽  
Content Type ◽  
Nano Fluid ◽  
Layer Flow ◽  
Particle Shapes ◽  
Nano Fluids

Purpose The purpose of this study is to theoretically probe the shape impacts of nano-particle on boundary layer flow of nano-fluid toward a stretching cylinder with heat-transmission effects. The base fluid used for this study is pure water, and aluminum oxide nano-particles are suspended in it. Four different shapes of nano-particle, namely, cylindrical, brick, platelets and blades, are considered to carry out the study. Design/methodology/approach The problem is modelled mathematically and the nonlinear system of equations is attained by using appropriate transmutations. The solution of transmuted equations is achieved by utilizing a shooting technique with Fourth-Fifth order Runge–Kutta Fehlberg scheme. Numerically attained results are elucidated through graphs and tables which are further compared under limiting cases with existing literature to check the validity of the results. Findings It is observed that fluid velocity and temperature of cylindrical shaped water nano-fluids are more than the nano-fluid having brick-shaped nano-particles. Moreover, it is seen that the nano-fluids suspended with platelets-shaped nano-particles have higher velocity and temperature than the nano-fluids containing blade-shaped nano-particles. The curvature parameter and nano-particles volume fraction have increasing effects on flow velocity and temperature of nano-fluids containing all types of nano-particle shapes. Originality/value Numerous authors have examined the impacts of nano-particle shapes on characteristics of heat transfer and fluid flow. However, to the best of the authors’ knowledge, the shape impacts of nano-particles on boundary layer flow of nano-fluid toward a stretching cylinder with heat-transmission effects have not been discussed. So, to fulfill this gap, the present paper explicates the impacts of various nano-particle shapes on Al2O3–water-based nano-fluid flow past a stretching cylinder with heat-transfer effects.

Thermal Conductivity of Nanofluids

2013 ◽  
Vol 757 ◽  
pp. 111-137 ◽  
Author(s):  
Amit Sobti ◽  
R.K. Wanchoo
Keyword(s):  
Thermal Conductivity ◽  
Critical Analysis ◽  
Base Fluid ◽  
Size Range ◽  
Volume Fraction ◽  
Nano Particles ◽  
Research Groups ◽  
Single Model ◽  
Nano Fluid ◽  
Enhanced Thermal Conductivity

Enhanced thermal conductivity of nanofluids compared to that of the base fluid has received attention of many researchers in the last one decade. Experimental data on thermal conductivity of nanofluids using varied nanoparticles in the size range 10-100 nm have been reported. However, there is lot of variance in the data and needs critical analysis. Many models have been proposed by various research groups for predicting the thermal conductivity of nanofluids. Due to complexity of various parameters involved (size, % volume fraction, specific surface area and the type of nano particles, pH of nano fluid, thermal conductivity and viscosity of base fluid) no single model can be used for predicting the thermal conductivity of nanofluids. Inconsistent and conflicting results are reported on the enhanced thermal conductivity of nanofluids. Further, insufficient understanding and inconclusive mechanism behind enhanced thermal conductivity requires further attempt to work in this field. This article critically reviews the available literature on thermal conductivity of nanofluids.

scholarly journals Performance Improvement of Base Fluid Heat Transfer Medium Using Nano Fluid Particles

2020 ◽  
Vol 23 (4) ◽  
pp. 235-243
Author(s):  
T. Sathish
Keyword(s):  
Heat Transfer ◽  
Performance Improvement ◽  
Base Fluid ◽  
Flow Problem ◽  
Thermal Characteristics ◽  
Nano Particles ◽  
Simulation Tool ◽  
Heat Transfer Medium ◽  
Nano Fluid ◽  
Nano Fluids

Base fluids like water, ethylene glycolandengineoilare conventionally used as a heat transfer medium. The performance of heat transferred is improved in the conventional fluids with the addition of Nano particles. Hence, this paper considers the forced conventional flow problem over the base fluid within a uniform heated tube placed on a wall. The analysis of heattransferco-efficientis done through a constant Reynoldsnumberfor both Nano and base fluid with a simulation tool. Further, a comparative analysis is carried out with heat transfer coefficient over the base and various Nano fluids. It is seen that the Nano fluids has a better performance due to its better thermal characteristics under standard conditions.

Conjugate Heat Transfer in a Hexagonal Micro Channel Using Hybrid Nano Fluids

2016 ◽  
Author(s):  
Shreyas S. Hegde ◽  
Narendran Ganesan ◽  
N. Gnanasekaran
Keyword(s):  
Heat Transfer ◽  
Surface Roughness ◽  
Heat Transfer Coefficient ◽  
Pressure Drop ◽  
Conjugate Heat Transfer ◽  
Nano Particles ◽  
Micro Channel ◽  
Nano Fluid ◽  
Nano Fluids ◽  
Effect Of Surface

Research is being focused on the use of micro channels with nano fluids as the heat sinks. This requires fundamental understanding of the heat transfer phenomenon in micro channels. The objective of this paper is to present results from a numerical study on laminar forced convection in a Hexagonal Micro Channel (HMC) heat sink. In particular, the numerical study is carried out using a single phase model. The fluid considered is Alumina-Copper hybrid Nano fluid. The performance of Al2O3+Cu+water is compared with Al2O3+water nano fluid and pure water with different volume fractions. The solid region of the channel is assumed as aluminum with a hydraulic diameter of 175μm. The solid and fluid regions of the micro channel are discretized using finite volume method by combining Navier Stokes equation and energy equation for conjugate heat transfer. The thermo physical properties for alumina nanoparticles are calculated by considering it as a spherical particle of 45nm diameter. The effect of surface roughness on convective heat transfer coefficient and pressure drop for the case of nano fluids is also considered. The analysis is further extended by adding pulsating input and by varying the velocity sinusoidally. The Brownian motion of nano particles is increased to study the efficiency of the heat sink. This ensures all the nano particles are in suspension and the randomness increases the micro convection in the fluid. Incorporating the pulsating flow increases the dispersion of the heat in the nano fluid at a faster rate and also decreases particle settlement in laminar flow. The combined effect of surface roughness and pulsating flow accounts for the change in the velocity profile and thermal boundary layer of the channel. Also the effect of surface roughness ranging from 0.2–0.6 is attempted and the variations in pressure drop, Nusselt number, and heat transfer coefficient are studied. The influence of hexagonal geometry and its interaction with alumina nano fluids is intensively studied by evaluating a three dimensional conjugate heat transfer model. The effect of side wall angle of 45°, 50° and 55° are computed to relate the velocity function with pressure drop, surface roughness and local heat transfer coefficient. The variation of Nusselt number with very low volume fraction of nano particles with a minimal amount of pressure drop is also presented.

Effect of the Concentration of Zinc Oxide Nano Fluid for Enhancing the Performance of Stirling Engine

2015 ◽  
Vol 1123 ◽  
pp. 274-280
Author(s):  
Suyitno ◽  
Danardono Dwi Prija Thahjana ◽  
Sutarmo ◽  
Syamsul Hadi ◽  
Alfaitory Emhemed
Keyword(s):  
Thermal Conductivity ◽  
Zinc Oxide ◽  
Physical Properties ◽  
Specific Heat ◽  
Stirling Engine ◽  
Nano Fluid ◽  
Nano Material ◽  
Nano Fluids

The development of nano fluid is very promising as a new fluid because it shows superior properties. However, the distinctive properties of the fluid depend on the concentration of nano material besides its designation also needs to be reviewed. Therefore, this study aims to develop the ZnO-based nanofluid for improving the performance of Stirling engine. The nano fluids were prepared by suspending nanorod ZnO into ethanol with various concentrations. Physical properties of the nano fluid such as density, thermal conductivity, viscosity, and specific heat were measured. Meanwhile, the performance of the Stirling engine using ZnO-based nano fluid was investigated including power, torque, and efficiency. The results showed that the performance of the Stirling engine increased along with the increase of the concentration of ZnO nano fluid to 5% and then decreased above this point. The addition of nano fluid up to a concentration of 5% was able to produce the efficiency of Stirling engine at 3.86% or an increase by 51.7% when compared with the previous Stirling engine.

scholarly journals Improvement of Drag Reduction for Water Flow in Pipe Based Nanofluid

2020 ◽  
Vol 27 (1) ◽  
pp. 44-49
Author(s):  
Thamer Jasim Mohammed ◽  
Ellaf Khaled Abbass
Keyword(s):  
Drag Reduction ◽  
Flow Rate ◽  
Tap Water ◽  
Pure Water ◽  
Nano Particles ◽  
Nano Fluid ◽  
Friction Factors ◽  
Stainless Steel Pipe ◽  
Maximum Drag Reduction ◽  
Nano Fluids

In the present work, the effect of Nano fluids as drag reducing agents for water flowing in pipelines was studied. Tap water was chosen to be the tested liquid and the Nano fluid was a dilute solution of water and titanium dioxide (TiO2) Nano particles which was used at five different concentrations (50, 100, 150, 200, and 250) ppm. The test section of the experimental setup consisted of a stainless steel pipe of 29.6 mm I.D (DN25) and 1.2 m long.  Water was pumped with eight different flow rates (1.0 - 8.0 m3/hr) through the pipe at room temperature (35±1) o C. The effect of the nano particle concentration and the flow rate (or Reynolds number) on percentage drag reduction (%Dr) and flow rate increases (%FI) was examined. Generally, a gradual increase of %Dr &%FI was observed with increasing the NP concentration and bulk velocity. The highest TiO2 concentration of 250 ppm and Re.No. of 106230 offered the maximum drag reduction which was 29.7%. Friction factors were also calculated from experimental data. Their values for pure water transported lies near or at Blasuis asymptote. While by introducing the additives, their values were positioned below Blasuis asymptotes towards Virk maximum drag reduction asymptotes.

Sign in / Sign up

Export Citation Format

Share Document