In Thermal systems, Heat transfer fluids play a significant role. But conventional temperature transfer fluids have poor temperature transfer features. Many researches are created in order to improve the thermal properties of regular fluids. The improvement of thermal conductivity of regular fluids by micro-sized solid particles will not result in a valuable change. Therefore, Nanoparticles are put into it to create sizeable heat transfer liquids. Metal oxide nanoparticles i.e. Al2O3 is confusing with water and thermal conductivity of the blend is certainly investigated at different temperature ranges. It is discovered that the thermal conductivity boosts by 5%. The evaluation summarizes that the effective thermal conductivity of the Nano fluids boosts beyond 55°C

Sowndarajan, S

Subakaran, C

V P, Sureshkumar

Y.G, STERBIN JESO

International Research Journal of Automotive Technology (IRJAT)

        
 
 
 
 
 
 
 
INTERNATIONAL RESEARCH JOURNAL OF AUTOMOTIVE TECHNOLOGY (IRJAT) 
 
http://www.mapletreejournals.com/index.php/IRJAT                   
Received 8 March 2018                    ISSN 2581-5865   
Accepted 19 March 2018                      2018; 1(2);22-28 
Published online 30 March 2018 
Investigation of Thermal Conductivity of water with Al2O3 
Nanoparticles 
V. P Suresh kumar 1*, Y.G. Sterbin Jeso2, C. Subakaran 2, S. Sowndarajan 2 
1Asst Professor, Dept of Mech Engg, P.A College of Engg and Tech, Pollachi, TamilNadu, India. 
2U. G Scholar, Dept of Mech Engg, P.A College of Engg and Tech, Pollachi, TamilNadu, India. 
*Corresponding author E-Mail ID: vpsuresh4@gmail.com, Mobile: 9698661167 
ABSTRACT 
In Thermal systems, Heat transfer fluids play a significant role. But conventional temperature 
transfer fluids have poor temperature transfer features. Many researches are created in order to 
improve the thermal properties of regular fluids. The improvement of thermal conductivity of 
regular fluids by micro-sized solid particles will not result in a valuable change. Therefore, 
Nanoparticles are put into it to create sizeable heat transfer liquids. Metal oxide nanoparticles i.e. 
Al2O3 is confusing with water and thermal conductivity of the blend is certainly investigated at 
different temperature ranges. It is discovered that the thermal conductivity boosts by 5%. The 
evaluation summarizes that the effective thermal conductivity of the Nano fluids boosts beyond 
55°C. 
Keywords: Heat transfer, Thermal conductivity, Al2O3, Metal oxide.  
1. INTRODUCTION 
Most significant industries including microelectronics, production, metrology, etc have 
already been applied in the cooling procedure by way of fluids. With raising thermal loads that 
want developments in cooling the brand new higher power output devices with quicker speeds and 
sized feature, the traditional heat transfer fluids, such as for example water, engine essential oil, 
ethylene glycol, etc. [14]., demonstrate the relative low warmth transfer performance. The very 
best potential alternative way of the heat transfer improvement is with the addition of solid 
additives in base fluid i.e. thermal conductivity of metallic or non-metallic solids may have two 
orders of magnitude greater than the conventional fluids. The enhancement of thermal 
conductivity of conventional fluids with the suspension of solid particles, such as for example 
micrometer-sized particles, has been popular for more than a century. The recent progress in 
components technology has managed to get possible to create nanometer-sized particles that may 
overcome these above complications. The innovative fluids suspended with nanometer-sized solid 
particles can transform the transportation and thermal properties of the base fluid, and make the 
fluid stable [1]. 
Thermal Conductivity values are essential every time usually to evaluate the heat transfer 
problem. Furthermore, thermal conductivity is normally a house of fundamental curiosity in 
developing the idea of fluids. The use of heat exchanger gadgets was increasing daily because of 
vast applications in commercial sectors. But conventional high temperature transfer fluids have 
got poor physical properties which worse the functionality of engineering apparatus. The thermal 
conductivity of typical high temperature transfers liquids such as water, propylene glycol, 
ethylene glycol or engine oil can be improved by the work of Ahuja [2], by adding 
micro/millimeter sized suspended particles in it. Adding suspended particles of micro/millimeter 
V.P.Suresh kumar et al. / International Research Journal of Automotive Technology 2018; 1(2): 22-28 
sized particles have some drawbacks such as sedimentation, fouling, erosion and improved 
pressure drop and it was considered not suitable for heat transfer medium. The heat transfer fluids 
suspended by nanometer sized particles called Nano fluids is developed to overcome the above 
drawbacks. Choi [3] at Argonne National Laboratory, USA showed that the thermal overall 
performance could be improved by adding nanoparticles in conventional fluids. Numerous 
investigations by Choi [3] have demonstrated that, actually for low concentrations of suspended 
nanoparticles in fluid exhibit high thermal conductivity.  
The Al2O3 nanoparticles were selected to prepare the water-based Nano fluids in this 
scholarly study because of their chemical stability. Preparation of Nano fluids may be the key 
stage in the use of nanoparticles for steady Nano fluids. Two types of methods have already been 
employed in creating Nano fluids: the single-step technique and the two-step technique. The 
single-step technique is an activity combining the planning of nanoparticles with the formation of 
Nano fluids, that the nanoparticles are straight made by the physical vapor deposition technique or 
the liquid chemical substance technique (Choi, 1995, Eastman et al., 1997) [4]. The procedures of 
drying, storage, transport, and dispersion of nanoparticles could be avoided, therefore the 
aggregation of nanoparticles is certainly minimized and the balance of fluids is improved. But a 
drawback of the technique is that just low vapor pressure fluids are appropriate for the process. 
The applications are tied to it of the technique. The two-step way for preparing Nano fluids is 
certainly an activity by dispersing nanoparticles into base liquids. Eastman et al. (1997), Lee et al. 
(1999) , and Wang et al. (1999) [5] used this method to produce the Al2O3 Nano fluids. 
Nanoparticles used in the technique are produced seeing that a dry out powder by inert gas 
condensation firstly, chemical substance vapor deposition, mechanical alloying, or the other 
suitable methods prior to the Nano-sized powder is then simply dispersed into a fluid in the next 
processing stage. This step-by-step technique isolates the planning of the Nano fluids from the 
planning of nanoparticles. As a total result, aggregation of nanoparticles usually takes place in 
both steps, along the way of drying especially, storage, and transport of nanoparticles. The 
aggregation would not only lead to the clogging and settlement, but affect the thermal properties 
also. The methods such as for example ultrasonic agitation or the addition of surfactant in to the 
fluids can be used to reduce particle aggregation and improve dispersion behavior. Since Nano 
powder synthesis methods have been commercialized, there are potential financial advantages in 
using the two-step synthesis technique. But a significant problem that should be solved may be the 
stabilization of the suspension to prepare ourselves. 
2. NOMENCLATURE   
       Cp  Specific heat capacity, J/kg K 
            d               Particle diameter, m   
k   Thermal conductivity, W/mK  
      kb             Boltzmann constant, J/K 
            n              Shape factor, dimensionless  
      T   Temperature, K  
Greek Symbol 
           β   Ratio of nanolayer thickness to particle radius, dimensionless 
           Ø     Volume concentration, % 
           μ              Absolute viscosity, Ns/m2 
           ρ              Density, kg/m3 
           ψ               Sphericity, dimensionless 
 
V.P.Suresh kumar et al. / International Research Journal of Automotive Technology 2018; 1(2): 22-28 
Subscripts 
           bf              Base Fluid 
           cp        Centi Poise 
           eff        Effective 
           nf       Nanofluid 
           P        Particle 
           r        Relative 
 
3. THEORETICAL INVESTIGATION 
3.1 Thermal Conductivity   
From the experimental results of many researchers, it was find that the thermal 
conductivity of nanofluids was changes by the base fluids of nanoparticles, the volume of 
concentration, shape of nanoparticles and the temperature. The Maxwell [6] was the first model to 
determining the thermal conductivity of liquid-solid suspensions. The effective thermal 
conductivity is given in equation (1): 
2 2( )
2 ( )
p f p f
eff f
p f p f
k k k k
k k
k k k k


  

  
                              (1) 
kp, kf, and Ø were the thermal conductivity of the particle and base fluid and the particle 
volume fraction in the suspension, respectively. 
In advance to Maxwell equation, the Hamilton and Crosser model [7] was used for 
determining the effective thermal conductivity of a two-phase mixture. The model was given in 
equation (2): 
( 1) ( 1)( )
( 1) ( )
p f p f
eff f
p f p f
k n k n k k
k k
k n k k k


    

   
               (2) 
where n is defined as n=3/ Ø and Ø was the sphericity. For the spherical shape particle, the 
sphericity (Ø) is 1.  
In addition, Bruggeman [8] analyzed the interactions among randomly distributed particles 
by using the mean field approach. The Bruggeman model [9] was given in equations (3):    
1
[(3 1) (2 3 ) ]
4 4
b
eff p b
k
k k k      
              (3)                                                                                                                                                   
where keff was the thermal conductivity of liquid with particle suspension,  was the 
volume fraction of particles and kp & kb were the thermal conductivities of the base fluid and the 
particles respectively. 
 Timofeeva et al. [10] has expressed a mathematical model. The expressed model can be 
written as in equation (4) & (5): 
3( )
/ 1
2
p bf
nf bf
p bf
k k
k k
k k

 

                                         (4) 
                               
V.P.Suresh kumar et al. / International Research Journal of Automotive Technology 2018; 1(2): 22-28 
p
bf
k
x
k

        
1
2 2
p bf
p bf
k k x
k k x
 
  
 
                          (5)                                                                             
 The dependence of thermal conductivity to temperature and concentration were proposed 
by Vajjha and Das [11]. The empirical model was proposed in equation (6): 
 
2( ) ( ) ( )nfk A B T C T                                       (6) 
 The coefficients A, B, C were polynomial functions of concentration. From all the above 
study, it can be seen that there are no general models to explain the strange behavior of the 
nanofluids including the viscosity and also the effective thermal conductivity. No reliable theory 
has predicted for the thermal conductivity of nanofluids. The significant differences between 
experimental data and theoretical models demonstrate the necessity of experimental workings. 
 
4. PREPARATION OF NANOFLUIDS 
 During the experiment we dispersed the Al2O3 Nanoparticle with the average diameter of 
25nm and particle density of 3.7 g/cm3 into 100ml of the de-ionized water [16]. Oxide-particle 
volume concentrations are usually below 5% to be able to maintain moderate viscosity raises [12]. 
 
 
 
 
 
 
 
 
      Fig. 1 Preparation of Nano fluids 
5. THERMAL CONDUCTIVITY MEASUREMENT OF NANOFLUIDS 
In our study, hot-wire method was used to gauge the thermal conductivity of Nano fluids. 
The accuracy of the equipment was found to be  0.1 of readings. For measurement of the thermal 
conductivity the vessel with tested sample was positioned within the temperature managed bath 
and sample temperature was checked by a thermocouple inserted into the vessel. All of the data 
were used 3 times and the common of 3 values was used for analysis [15]. Figure 2 shows the 
apparatus for measuring thermal conductivity of fluids in this apparatus Nichrome wire was used 
as a hot-wire with the diameter of 0.38mm. When a uniform voltage was supplied to   the circuit, 
the electric resistance of the Nichrome wire rises with the temperature of the wire, and the voltage 
output was measured by an A/D converting system. Details of this method can be found in other 
literature [13]. The thermal conductivity was calculated, as in equation (7). 
Weighting the 
solid and liquid 
phase. 
 
Mixing the 
mixture with 
Magnetic stirrer. 
Uniformly 
dispersion with 
ultrasonic 
vibrator. 
Thermal 
Conductivity 
measurement. 
V.P.Suresh kumar et al. / International Research Journal of Automotive Technology 2018; 1(2): 22-28 
2 1
ln( )
4 ( )
q
k t
T T


                                                  (7) 
Where, 
k = Thermal conductivity of fluid 
q = Heat supplied 
T1 = Initial temperature of fluids 
T2 = Final temperature of fluids 
 t = Time taken for the temperature rise 
 
                                                     Fig. 2 Thermal conductivity measuring apparatus for fluids 
 
6. RESULTS AND DISCUSSION 
The graph shows the comparison of thermal conductivity of Al2O3 value to the standard 
thermal conductivity value at different temperatures. It is found that thermal conductivity of Nano 
fluid containing Al2O3 increases on comparing with the standard liquid. The increase in thermal 
conductivity ranges from 4-6% which can make some valuable change in heat transfer properties. 
 
 
Fig.3 Temperature vs Thermal conductivity of Al2O3 
 
V.P.Suresh kumar et al. / International Research Journal of Automotive Technology 2018; 1(2): 22-28 
7. CONCLUSION        
The effect of temperature on the enhanced effective thermal conductivity of Nano fluids is 
important for theoretical understanding and needs to be considered for the model development. 
The thermal conductivity of the nanoparticle suspensions is dependent on the size of the 
nanoparticles, the interaction between the particle and liquid, and the thermal conductivity of the 
base fluid. In the current study, the Thermal conductivity of Nano fluids containing Al2O3 
Nanoparticle is experimentally investigated. The experiments are made to find thermal 
conductivity by the suitable apparatus at various temperature ranging from 50-60oC. The 
observations are tabulated and analyzed. It is to be found that Thermal conductivity rate of 
enhancement increases with in temperature. The thermal conductivity is found to be increased by 
5% on adding Al2O3 Nanoparticle and the highest enhancement is found beyond 55°C.This can 
minimize some wear of the thermal equipment and hence increase some performance of thermal 
system. 
REFERENCES 
1.  Fei Duan, Thermal Property Measurement of Al2O3-Water Nanofluids School of 
Mechanical and Aerospace Engineering, Nanyang Technological University Singapore, p.no.336-
338. 
2. Ahuja A.S., Augmentation of heat transport in laminar flow of polystyrene suspension, 
Experiments and results, J.Appl. Phys., 1975, p. 3408–3416. 
3. Choi S.U.S., Enhancing thermal conductivity of fluids with nanoparticles, ASME FED. 
231/MD., 1995, p. 99–103. 
4. Choi SUS. Development and applications of Non-Newtonian flows’. In: Singer DA, Wang 
HP, editors. Development and application of non-Newtonian flows. FED 231. New York: ASME; 
1995., p.99-105. 
5. Eastman, J.A.; Choi, S.U.S.; Li, S.; Thompson, L.J. & Lee, S. (1997). Enhanced thermal 
conductivity through the development of nanofluids. Mater. Res. Soc. Symp. Proc.,457, 3-11.  
6. Maxwell J.C., A Treatise on Electricity and Magnetism. 2nd Ed. Cambridge, UK:Oxford 
University Press, 1904., p.10-20. 
7. R.L. Hamilton, O.K. Crosser: Thermal conductivity of heterogeneous two-component 
systems, Ind Eng Chem Fundam 1.,1962., p.187–191 
8. D.A.G. Bruggemen: Berechnung Verschiedener Physikalischer Konstanten von 
Heterogenen Substanzen, I. Dielektrizitatskonstanten und Leitfahigkeiten der Mischkorper aus 
Isotropen Substanzen, J. of Ann. Phys 24.,1935., p. 636–679. 
9. R.S. Vajjha, D.K. Das, Measurement of thermal conductivity of Al2O3 nanofluid and 
development of a new correlation, T. (Ed.), Proceedings of 40th Heat Transfer and Fluid 
Mechanics Institute, Sacramento, Marbach, CA.,2008., p.14. 
10. E. V. Timofeeva, A. N. Gavrilov, J. M.cCloskey and Y. V. Tolmachev, S. Sprunt, L.M. 
Lopatina, J. V. Selinger: Thermal conductivity and particle agglomeration in alumina nanofluids: 
Experiment and theory, Physical Review E 76.,2007.,p.1–15. 
 
 
V.P.Suresh kumar et al. / International Research Journal of Automotive Technology 2018; 1(2): 22-28 
11. R.S. Vajjha, D.K. Das, Measurement of thermal conductivity of Al2O3 nanofluid and 
development of a new correlation, T. (Ed.), Proceedings of 40th Heat Transfer and Fluid 
Mechanics Institute, Sacramento, Marbach, CA.,2008., p.14. 
12. Thermal conductivity, viscosity and stability of Al2O3-diathermic oil nanofluids for solar 
energy systems. Gianpiero Colangelo, Ernani Favale, Paola Miglietta, Marco Milanese, Arturo de 
Risi. Universit_a del Salento, Dipartimento di Ingegneria dell'Innovazione, Via per Monteroni, 
73100 Lecce, Italy.,2016.,p.137-143. 
13. Carslaw, H.S., and Jaeger, J.C., Conduction of Heat in Solids, 2nd Edition, Oxford 
university press, New York, 1959, p. 510. 
14. Fei Duan, Thermal Property Measurement of Al2O3-Water Nanofluids School of 
Mechanical and Aerospace Engineering, Nanyang Technological University Singapore, p.no.335. 
15. Kwek, D.; Crivoi, A. & Duan, F. (2010). Effects of temperature and particle size on the 
thermal property measurements of Al2O3-water nanofluids. J. Chem. Eng. Data, 55, 5690-5695. 
16. Sakamoto, M.; Kanda, Y.; Miyahara, M. & Higashitani, K. (2002). Origin of long-range 
attractive force between surfaces hydrophobized by surfactant adsorption. Langmuir, 18, 5713-
5719. 
17. Masuda H. Alteration of thermal conductivity and viscosity of liquid by dispersing ultra-
fine particles (dispersion of y-A12O3, SiO2, and TiO2 ultrafine particles). Netsu Bussei 1993, 
p.27–33. 
 


Investigation of Thermal Conductivity of water with Al2O3 Nanoparticles

https://mapletreejournals.com/index.php/IRJAT/article/download/11/11

Investigation of Thermal Conductivity of water with Al2O3 Nanoparticles

Abstract

Similar works

Full text

Available Versions

International Research Journal of Automotive Technology (IRJAT)