Fin Design for Maximum Thermal Dissipation
ME 450: Computer Aided Engineering Analysis
Instructor: Dr. Nema
Group Members: Wei-Yuan Chu, Brad Holtsclaw, Nick Metzger,
Breanne Walters
Objectives
Maximize Thermal Dissipation by Designing a Fin System that will Draw Heat Away from the Engine Casing
Using Aluminum Alloy and Carbon Steel as Materials, we will analyze which material makes a better fin.
Introduction
Engine is used to run a small blower It is assumed that the motor casing will be
subjected to cooling by a fan or other suitable ventilation.
Main area of concern is drawing heat into the fin system in order to dissipate it into the air.
Complete AssemblyArea of Interest
Theoretical Background
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Theoretical Background (Cont.)
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Model Details (Solid Modeling)
Solid Models were created in Pro-Engineer and Converted to IGES Files to Import into Ansys
Model Details (Type I)
SOLID 92 Element Type
5,829 Elements 10,706 Nodes
Model Details (Type II)
SOLID 92 Element Type
16,196 Elements 29,355 Nodes
Model Details (Type III)
SOLID 92 Element Type
16,196 Elements 29,355 Nodes
Boundary Conditions
Temperature of 65.56oC applied to Internal Surface to Simulate Operating Conditions
Boundary Conditions (Cont.)
Ambient Temperature of 10oC
Film Coefficient of 100 W/m*oC (for cooling airspeed of 10 m/s)
Results and Discussion:S.S. Temperature Distribution (Type I) – Steel Top Fins
Carbon Steel Top Fins
Max. Temp. in Fins is 55.078oC
Results and Discussion: S.S. Temperature Distribution (Type I) – Aluminum Top Fins
Aluminum Top Fins
Max. Temp. in Fins is 60.218oC
Results and Discussion: S.S. Temperature Distribution (Type II) – Steel Top Fins
Steel Top Fins
Max. Temp. in Fins is 50.885oC
Results and Discussion: S.S. Temperature Distribution (Type II) – Aluminum Top Fins
Aluminum Top Fins
Max. Temp. in Fins is 55.777oC
Results and Discussion: S.S. Temperature Distribution (Type III) – Steel Top and Side Fins
Steel Top and Side Fins
Max. Temp. in Fins is 50.885oC
Results and Discussion: S.S. Temperature Distribution (Type III) – Aluminum Top and Side Fins
Aluminum Top and Side Fins
Max. Temp. in Fins is 55.777oC
Results and Discussion: Transient Response(Type III) – Aluminum Top and Side Fins
Results and Discussion: Top Fin Design Comparison Solutions
Length (m) thickness (m)width (m) Lc t P h k0.019 0.002 0.210 0.020 0.002 0.423 100.000 53.000
Af Ab At m nf θb qt0.008 0.013 0.064 43.644 0.800 0.632 55.410 651.498
Length (m) thickness (m)width (m) Lc t P h k0.019 0.002 0.210 0.020 0.002 0.423 100.000 252.000
Af Ab At m nf θb qt0.008 0.013 0.064 20.015 0.900 0.290 55.410 679.434
Steel Top Fins
Aluminum Top Fins
Temperature Distribution (Top Fins)
0
0.2
0.4
0.6
0.8
1
1.2
0 0.01 0.02 0.03 0.04 0.05
Length (m)
θ/θb
Aluminum
Steel
Results and Discussion: Side Fin Design Comparison Solutions
Length (m) thickness (m)width (m) Lc t P h k0.051 0.004 0.229 0.053 0.004 0.465 100.000 53.000
Af Ab At m nf θb qt0.024 0.010 0.083 30.959 0.580 1.173 55.410 583.892
Length (m) thickness (m)width (m) Lc t P h k0.051 0.004 0.229 0.053 0.004 0.465 100.000 252.000
Af Ab At m nf θb qt0.024 0.010 0.083 14.198 0.850 0.538 55.410 801.786
Steel Side Fins
Aluminum Side Fins
Temperature Distribution (Side Fins)
0
0.2
0.4
0.6
0.8
1
1.2
0 0.01 0.02 0.03 0.04 0.05
Length (m)
t/tb
Aluminum
Steel
Results and Discussion: Heat Transfer Comparison for Type III Design
Top Fins (W) Top Fins (W)Side Fins (W) Side Fins (W)Total (W) Total (W)
Δq (W) 245.8301481.220 1235.390
583.892651.498
Total Heat Transferred by Aluminum Fins Total Heat Transferred by Steel Fins679.434801.786
Impact Statements The Addition of Fins will Aid in the Heat
Dissipation from the Motor Casing, making the Part More Safe for General Use
Motor Casing with Type III Fins Will have a Reduced Surface Temperature and Less of a Chance of Overheating the Interior Electronics and Causing a Fire
Conclusions Total Heat Transferred from Aluminum
Fin is 245.83 W Greater than that from the Steel Fin.
Efficiency for Aluminum Fin is Greater than that of Steel.
Aluminum is the Best Choice for the Fin Material.
References
Nematollahi, Khosrow. "Oncourse, ME 450." Scheduled Reading and Assignments. IUPUI. 23 Apr 2007
<https://oncourse.iu.edu/access/content/user/knematol/Filemanager_Public_Files/ME450LectureNotesCh13r>.
Incropera, Frank, David Dewitt, and Theodore Bergman. Fundamentals of Heat and Mass Transfer. 6th. Hoboken NJ: Wilet & Sons, 2007.
Rengifo, Gustavo. "Oncourse, ME 546." ME 546 Resources, Project #1. IUPUI. 23 Apr 2007 <https://oncourse.iu.edu/access/content/group/SP07-IN-ME-546-
26532/Lab%20Projects/Project%>.
Questions