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05/03/2023 Rochester Institute of Technology 1
Steady state thermal analysis of a 4-stroke single cylinder I.C.E fins
Varun BhaleraoDr. Ali Ogut
KGCOE - Department of Mechanical EngineeringRochester Institute of Technology
Introduction• Temperature inside the
combustion chamber goes up to 1500°C
• Metal temperature needs to be brought down to ensure good efficiency
• High temperature burns the oil inside the cylinder
• Decreases the efficiency and lowers the lifespan of the engine
• Fins are an efficient way of cooling along with a heat exchanger Figure 1: Failure of the piston due to high temperature
05/03/2023 Rochester Institute of Technology 3
ObjectiveMost efficient combination of material and fin geometry by performing thermal analysis of fins having natural convection cooling:• Analysis of curved and rectangular fins
for the surface temperature and heat flux
• Compare different fin materials• Grey cast iron• Aluminium alloy 6061• Aluminium alloy 6060
• Curved fins: 37 mm length and 12 mm radius
• Rectangular fins: 57.8 mm * 60.8 mm • Thickness of fins: 1.5 mm
Figure 2: Rectangular fins Figure 3: Curved fins
Table 1: Material properties
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Mesh• The lowest element size that was
accepted: 0.001• Tested various meshes
• Coarse and fine mesh for an element size of 0.002
• Coarse and fine mesh for an element size of 0.001
• The temperature and heat flux for every fin remained same for every mesh
• Mesh independence was observed
Figure 4: Coarse mesh (0.002 element size)
Figure 5: Fine mesh (0.001 element size)
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Analysis
• In steady state system, defined the temperature of 300°C in the combustion chamber
• Set the ambient temperature to 22°C
• Allowed the system to go under natural convection cooling for 10 seconds
• Calculated the average temperature and the heat flux for various combinations of fins for the 2 geometries and 3 materials used
Figure 6 and 7: Temperature and heat flux distribution for curved fins (Aluminium alloy 6061)
Figure 8 and 9: Temperature and heat flux distribution for rectangular fins (Aluminium alloy 6061)
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Conclusion• Heat transfer rate of the rectangular fins is
higher than the curved fins in natural convection• For rectangular fins, Aluminium alloy 6060 has
the highest average temperature (294.34 °C) and heat flux (139071.1818 W/m2)• For curved fins, Aluminium alloy 6060 has the
highest average temperature (293.21 °C) and heat flux (128858.5 W/m2)• The rectangular configuration with the
Aluminium alloy 6060 for fins is the most efficient configuration• For rectangular and curved fins, Aluminium
alloy 6060 is the most efficient and grey cast iron is the least efficient.
265
270
275
280
285
290
295
Average surface temperature of curved fins for different materials
Grey Cast Iron Aluminium Alloy 6061Aluminium Alloy 6060
Tem
pera
ture
(°C)
105000
110000
115000
120000
125000
130000
135000
Average heat flux of curved fins for different materials
Grey Cast Iron Aluminium Alloy 6061Aluminium Alloy 6060
Heat
flux
(W/s
q.m
)
115000
120000
125000
130000
135000
140000
145000
Average heat flux for rectangular fins for different materials
Grey cast iron Aluminium alloy 6061Aluminium alloy 6060
Heat
flux
(W/s
q.m
)
265
270
275
280
285
290
295
Average surface temperature for rec-tangular fins for different materials
Grey cast iron Aluminium alloy 6061Aluminium alloy 6060
Tem
pera
ture
(°C)
05/03/2023 Rochester Institute of Technology 7
Thank you!