This document analyzes heat transfer of rectangular fins on an air-cooled internal combustion engine. The experiment aims to compare natural heat transfer of solid vertical fins to horizontal solid fins. The experimental setup includes an aluminum alloy fin attached to a cast iron cylinder bore filled with heated oil. Temperature measurements are taken at the fin root and tip over time for both vertical and horizontal fin orientations. Observations show faster cooling and higher initial root temperatures with vertical fins, indicating increased heat transfer effectiveness compared to horizontal fins. In conclusion, attaching a vertical fin rather than a horizontal fin can increase heat transfer coefficients and total heat dissipated.

1. HEAT TRANSFER ANALYSIS OF
RECTANGULAR FIN ON AN AIR COOLED IC
ENGINE
Done by :
Sri Lalitha Swathi .S (11011A0333)
Ashish Kumar.T (11011A0306)
Sankdeep. K (11011A0326)
Md Rassam (11011A0353)

2. INTRODUCTION
 Air cooled motorcycle engines release heat to the
atmosphere through convection.
 The rate of heat transfer depends upon the wind
velocity, geometry of engine surface, external
surface area and the ambient temperature
 To increase the convective heat transfer, one can
increase the effective surface area by using fins or
extended surfaces

3. OBJECTIVE
 The main objective of the project is to
analyse and compare the natural heat
transfer of solid vertical fin with that of
a horizontal solid fin by conducting
experiment.

4. EXPERIMENTAL SETUP
 The experimental setup consists of cast iron as cylinder bore of
an old splendour bike and aluminium alloy 6063 as the fin
material
 The fin was machined to a thickness of 5mm and to the length
of 25mm from the root of the fin.
 The cast iron cylinder is machined to an outer diameter of
70mm and inner diameter of 50mm.
 The height of the cylinder is 68mm. SAE 5W-20 engine oil is
used as the heated fluid element.
 Two heating coils of 50W each are used to heat the oil to
required temperature.
 Temperatures at different parts of the fin are measured with the
help of K-Type digital thermocouple. Infrared thermometer is
used to measure the oil temperature at regular intervals of time.
 Cotton wool, wooden lid are provided for insulation.

5. EXPERIMENTAL
PROCEDURE
 The hollow portion of the bore is filled with SAE5W20 engine oil
and heated to 210 ͦ C using two heater coils of 50W each.
 The power input is switched off and a wooden lid is placed
immediately above the cylinder and necessary insulation on the bare
cylinder is provided using cotton wool.
 Using K type thermocouple the temperatures at fin root and tip are
measured at 0,30,60,90 and 120 seconds. The readings are
tabulated.
 Also, the temperatures of oil at regular intervals are measured using
thermometer and are noted.
 The heat release is obtained from multiplying the heat capacity of
the heat storage liquid by the difference between initial and final
temperatures of oil at air velocity of 0km/hr. The experiments are
carried out at ambient temperature of 32 ͦ C.

6. GRAPHS OF READINGS
0
20
40
60
80
100
120
140
0 50 100 150 200 250
tip/roottemperature
oil temperature
tip/root temp vs oil temp for vertical fins
Toil vs Troot
Toil vs Ttip

7. 0
10
20
30
40
50
60
70
80
90
100
0 50 100 150 200 250
root/tiptemperature
oil temperature
root/ tip temp vs oil temp for horizontal fins
Temperature of root
Temperature of tip

8. OBSERVATIONS
 The temperature of oil which is initially heated to 210oC
decreased to 99oC in vertical fin as compared to 97 oC
in horizontal fin. This shows that cooling is faster with
vertical fins. This decrease in heat transfer may be
because of decrease in heat transfer coefficient.
 The root temperatures of vertical fins are more
compared to horizontal fins, which means that the heat
is transferred faster from the fluid to the fin root in
vertical cylinder than in horizontal cylinder.
 The temperature profiles observed for vertical and
horizontal fins are different. These profiles are more
elevated for vertical fins than for horizontal fins.

9. CONCLUSION
 When a vertical fin is attached , heat transfer coefficient
is changed to 15.32, as compared to the heat transfer
coefficient of 14.88 for horizontal fin, which is 2%
change
 The initial root temperatures of vertical fins are 50%
more as compared to the horizontal fins which means
there is increase in heat transfer rate from 142 W to 153
W , that is by 7%
 In case of vertical fin the efficiency and effectiveness
are increased by 8% because of increase in heat
transfer
 Total heat dissipated by 10 fins is increased from 27.53
to 39.35 when horizontal fins are replaced by vertical
fins

10. FUTURE SCOPE
As the orientation of the fin plays an important role in
heat transfer. There is scope of improvement in the heat
transfer of air cooled engine cylinder by choosing
vertical over horizontal by varying the
 Fin thickness of vertical fin
 Orientation of the fin
 Different types of engine oils can be used inside the
bore
 The present work is limited to experimental setup,
hence numerical techniques can also be used
 Different other fluids can be used as working medium
for future work

11. THANKYOU