CFD Analysis On Louvered Fin

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056
Volume: 04 Issue: 01 | Jan -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 1458
CFD ANALYSIS ON LOUVERED FIN
P.Prasad1, L.S.V Prasad2
1Student, M. Tech Thermal Engineering, Andhra University, Visakhapatnam, India
2Professor, Dept. of Mechanical Engineering, Andhra University, Visakhapatnam, India
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Abstract-Radiators are used to transfer thermal energy
from one medium to another for the purpose of cooling. They
are used for cooling internal combustion engines, mainly in
automobiles, railway locomotives, stationary power
generating plants etc. The radiator essentially transfers heat
from the coolant inside to the surrounding ambient air
enhancing performance of the engine. A model of radiator
with rectangular and louvered fins are developed using
Pro/Engineer and further CFD analysis is performed with
ANSYS 14.5 for a relative comparison of geometry of fins on
performance of the radiator. Aluminum alloy 6061 is
considered in either case to analyze the heat transfer
capabilities of louvered fins and rectangular fins.
Key words: Rectangular fin, louvered fin, Aluminum alloy
6061.
1. INTRODUCTION
All internal combustion engines generate a huge amount of
heat which is transferred tocylinderwalls,piston,valvesand
other components by conduction. This heat is carried away
by the coolant that circulates through the engine, especially
around combustion chamber and the cylinder head area of
the engine block. The coolant pumped through the engine
block, after absorbing the heat is circulated to the radiator
where the heat is dissipated to the surroundingatmosphere.
The coolant is then transferred back into the engine to
repeat the process. Two types of tubularfinnedradiators are
considered for the analysis, louvered fins and rectangular
fins respectivelymadeofAluminumalloy6061compared for
better heat transfer capabilities. The schematic diagram of
thermal resistance considered across the radiator tube is
shown in Fig. 1.
Eq 1
Eq 2
Eq 3
Eq 4
Fig-1: Thermal Resistance Diagram
Tin represents the inlet fluid temperature,Toutrepresentsthe
outlet fluid temperature, and Ta represents the ambient air
temperature. Durgesh Kumar Chavanetal.,[1]Experimental
tests of forced convective heat transfer in an Al2O3/water
nano fluid has experimentally been comparedtothatofpure
water in automobile radiator. The results demonstrate that
increasing the fluid circulating rate can improve the heat
transfer performance. Yadav et al.,[2] Performed numerical
parametric studies on automotiveradiatorandthemodeling
of radiator by two methods, namely finite differencemethod
and thermal resistance concept. In the performance
evaluation, a radiator is installed into a test-setup and the
various parameters including mass flow rateofcoolant,inlet
coolant temperature were varied. Junjanna et al., [3]
conducted the numerical analysis by modifying geometrical
and flow parameters like louver pitch, air flow rate, water
flow rate, and louver thickness, by varying one parameter
the results were compared. Manjunath et al., [4] Performed
high thermal resistance on the air side, the optimization of
such fins is essential to increase the performance of heat
exchanger. Optimization of louvered fin geometry in such
heat exchangers is essential to increase the heat transfer
performance and reduce weight and cost requirement.
Pooranachandran karthik et al., [5] Performed a numerical
analysis using fluent software for threechosendata from the
experiments. The increase in the flowrateof waterincreases
the total heat capacity of the water stream. The mass flow
rate of water has a better influence in increasing the heat
transfer at higher velocities of air.

2. MODELLING AND THERMAL ANALYSIS OF
RECTANGULAR AND LOUVERED FIN
Geometrical model of rectangular fin and louvered fin are
modeled with creo parametric 2.0 and the dimensions of
rectangular fin considered for the study is given below.
Rectangular fin thickness =0.25mm
Rectangular fin length=60mm
Rectangular fin width=15mm
Rectangular tube diameter=10mm
Number of fins considered =16
Rectangular fin height=30mm
Fig-2 :Meshing of rectangular fin
The solid model developed is subjected to meshing using
anysis for a rectangular fin as shown in Fig. 2. Thenumber of
nodes are 68013 and elements 32799 respectively.The
dimensions of louvered fin considered for the study are as
follows.
Louvered finned rectangular tube width=7.5 mm
Louvered finned rectangular tube length=15mm
Number of louvered fins considered =6
Fig-3: Louvered Fin Geometry
The solid model of louvered fin using Creo parametric 2.0 is
shown in Fig. 3. The meshed model of the same is shown in
Fig. 4. The number of nodes and elements were 463271 and
223429 respectively.
Fig-4: Louvered Fin Meshing
3. ALUMINUM ALLOY 6061 PROPERTIES
The Composition of Al6061 is given below
Mg =0.8 -1.2 %
Si =0.4-0.8 %
Cu =0.15-0.4 %
Cr =0.04-0.35 %
Mn =0.15 %
Fe =0.7 %
Zn =0.25 %
Ti =0.15 %
Al =95.85%-98.56%
Al6061 has the following advantages
 Excellent corrosion resistance to atmosphere
condition
 Good weldability and brazability
 Co efficient of linear thermal expansion
23.5x10-6m/0C
 Thermal conductivity 173 W/m. K
 Melting point is 5800C
 Modulus of elasticity is 70-80 G Pa.
 Poisson ratio is 0.33
4. THERMO PHYSICAL PROPERTIES OF FLUID
In automobile radiator water is used as cold fluid runs in the
tubes. This water does not have sufficient strength to fight
against cold weather. It becomes ice in cold weather so one
other fluid mixed with this water and name is this fluid is
ethylene glycol. This has sufficient antifreeze property to
make help to the water to stable liquid in cold weather.

Ethylene oxide reacts with water to produce ethyleneglycol
according to the chemical equation.
C2H4 + 2H2O → HO–CH2CH2–OH
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 25 50 75 100
50/50
Ethylene
glycol
with
water
mixture
Pure
water
Temperature ,0C
Thermalconductivity
,W/m.K
Fig-5: Variation of Thermal conductivity of 50/50
Ethylene glycol with water mixture and pure water with
temperature
Variation of thermal conductivity of 50/50 Ethylene glycol
with water mixture and pure water is shown in Fig. 5.
Ethylene glycol mixture certainly has a higher thermal
conductivity as compared to water and hence has a better
heat transfer capabilities as compared to water. The
presence of ethylene glycol could influence freezing
temperature of fluid also.
0
2
4
6
8
10
12
14
0 5 25 50 75
50/50
Ethylene
glycol with
water
mixture
Pure water
Temperature ,0C
Viscosity,cP
Fig-6: Variation of Viscosity of 50/50 Ethylene glycol with
water mixture and pure water with temperature
Fig.6 shows the variation of viscosity with temperature. It is
seen that variation of viscosityisfoundtobemarginal within
normal operating range as compared to water without
compromising much of pump work required.
5. RESULTS AND DISCUSSIONS
The temperature distribution and heat fluxdistributionfora
rectangular fin are shown in Fig. 7 and 8 respectively. A
localized high temperature is observed at coolant inlet
passage with not much temperature drop along the section
of the fin. The thermal conductivity of the aluminum and the
geometry of the fins are found to influence the temperature
distribution along the tubular radiator.
Fig-7: Temperature Distribution in rectangular fin
Fig-8: Total Heat Flux in rectangular fin
The maximum and minimum temperatures were found to
be 750C and 240C respectively as seen in Fig. 7. A maximum

heat flux of 31260 W/m2 was found at the entry region of
rectangular finned radiator as shown in Fig.8.
Fig-9: Temperature Distribution: Louvered fin
The temperature distribution across louvered fin radiatoris
shown in Fig. 9. The maximum and minimum temperature
was found to be 750C and 220C respectively. The
temperature distribution indicates that the geometry and
thermal properties of louvered fin is found to have a
profoundinfluenceontemperaturedistributionascompared
to rectangular fin. The region in proximity of the coolant
passage is found to be at a higher temperature with a
significant drop in temperature along the fin.
Fig-10: Total heat flux: Louvered fin
The heat flux density for louvered fin is shown inFig.10.The
maximum heat flux of 35657W/m2 is found to exist at the
entry region with few concentrated zones and there is a
proportionate drop in heat flux away from coolant flow
passages.
Fig-11: Static pressure in rectangular fin
The pressure distribution along the test section is shown in
Fig.11. The maximum static pressure of 34.6 N/m2 is found
to exist at the central coolant passages for a rectangular fin.
The rest of the test section is found to be exposed to a
nominal pressure of 12.6 N/m2.
Fig-12: velocity in rectangular fin
The velocity distribution of coolant through the coolant
passages is shown in Fig. 12 for test section withrectangular
fin. The maximum velocity of fluid distributions is found to
be 0.508 m/s.
Fig-13: Static pressure in Louvered fin

The static pressure distribution in louvered fin is shown in
Fig. 13. The pressure is found to be distributed across the
test section with a maximum pressure of 52.5 N/m2 found to
exist across the passages attached to the louvered fins at the
entry zone with marginal drop in pressure at the exit of the
test section.
Fig-14: Velocity distribution in Louvered fin
The velocity distribution in louvered fin is shown in Fig. 14.
The maximum fluid velocity of 1.41 m/s was estimated for
the coolant passing through the louvered cross section.
6.COMPARSIONOFRECTANGULARANDLOUVERED
FIN RESULTS
Parameter Rectangular
fin
Louvered fin
Heat Flux
(W/m2)
31260 35657
Velocity (m/s) 0.508 1.41
Temperature (K) 348 348
Total Heat
Transfer rate at
wall (W)
22253 45319
7. CONCLUSIONS
The comparative CFD analysis on rectangular and louvered
finned heat exchanger with 50/50 Ethyleneglycol andwater
mixture as working fluid reveals louvered fins exhibitbetter
heat transfer characteristicsascomparedtorectangularfins.
The heat transfer rate was found to be 49% more for
louvered fins as compared to rectangular fins. The velocity
was found to be significantly higher for louvered fins which
might be a contributing factor for enhanced heat transfer
rate in louvered fins.
8. REFERENCES
[1] Durgesh Kumar Chavan and Ashok T. Pise Sahin,
“Performance Investigation of an Automotive Car
Radiator Operated with Nano fluid as a Coolant,”
(2010).
[2] Gunnasegaran, “The effect of geometrical
Parameters on Heat Transfer Characteristics of
compact heat exchanger with Louvered Fins,”
(2012).
[3] Junjanna G.C, “Performance Improvement of a
Louver-Finned Automobile Radiator Using
Conjugate Thermal CFDAnalysis,”(2012),pp.2278-
0181.
[4] JP Yadav and Bharat Raj Singh, “Study on
Performance Evaluation of Automotive Radiator”
(2011), pp. 2229-7111.
[5] Jaya Kumar, “Experimental study and CFD Analysis
of Copper radiator for Passenger Cars,” (2016),
pp.778-782.
[6] Masoud Asadi, “Minimizing entropy generation for
louvered fins plate fin compact heat exchanger,”
(2013), pp.35-45.
[7] Manjunath, “Numerical Investigation of automotive
radiator louvered fin compact heat exchanger,”
(2014), pp.01-14.
[8] Paresh Machhar, Falgun Adroja,”Heat Transfer
Enhancement of Automobile Radiator with
TiO2/Water Nano fluid,” (2013), pp.2278-0181.
[9] Pooranachandran karthik, “Experimental and
numerical investigation of a louvered fin and
elliptical tube compact heat exchanger, (2015),
pp.679-692.

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