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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

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Objectives

Maximize Thermal Dissipation by

Designing a Fin System that will DrawHeat Away from the Engine Casing

Using Aluminum Alloy and Carbon Steel

as Materials, we will analyze whichmaterial makes a better fin.

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Introduction

Engine is used to run a small blower

It is assumed that the motor casing will besubjected 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.

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Complete AssemblyArea of Interest

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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

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Model Details (TypeI)

SOLID 92Element Type

5,829 Elements

10,706 Nodes

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Model Details (TypeII)

SOLID 92Element Type

16,196 Elements

29,355 Nodes

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Model Details (TypeIII)

SOLID 92Element Type

16,196 Elements

29,355 Nodes

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BoundaryConditions

Temperature of65.56oC applied to

Internal Surface to

Simulate Operating

Conditions

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BoundaryConditions (Cont.)

AmbientTemperature of10oC

Film Coefficient of100 W/m*oC (forcooling airspeedof 10 m/s)

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Resultsand Discussion:

S.S. Temperature Distribution

(TypeI) SteelTop Fins

Carbon

Steel TopFins

Max.

Temp. in

Fins is

55.078oC

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Resultsand Discussion:

S.S. Temperature Distribution

(TypeI) AluminumTop Fins

Aluminum

Top Fins Max.

Temp. in

Fins is60.218oC

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Resultsand Discussion:

S.S. Temperature Distribution

(TypeII) SteelTop Fins

Steel Top

Fins Max.

Temp. in

Fins is50.885oC

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Resultsand Discussion:

S.S. Temperature Distribution

(TypeII) AluminumTop Fins

Aluminum

Top Fins Max.

Temp. in

Fins is55.777oC

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Resultsand Discussion:

S.S. Temperature Distribution

(TypeIII) SteelTopand Side Fins

Steel Top

and SideFins

Max.Temp. in

Fins is50.885oC

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Resultsand Discussion:

S.S. Temperature Distribution

(TypeIII) AluminumTopand Side Fins

Aluminum

Top andSide Fins

Max.Temp. in

Fins is55.777oC

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Resultsand Discussion:

TransientResponse

(TypeIII) AluminumTopand Side Fins

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Resultsand Discussion:Top Fin Design

Comparison Solutions

Length (m) thickness width (m) Lc t P h k

0.019 0.002 0.210 0.020 0.002 0.423 100.000 53.000

Af Ab At m nf b qt

0.008 0.013 0.064 43.644 0.800 0.632 55.410 651.498

Length (m) thickness width (m) Lc t P h k

0.019 0.002 0.210 0.020 0.002 0.423 100.000 252.000

Af Ab At m nf b qt

0.008 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)

/b

Aluminum

Steel

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Resultsand Discussion: Side Fin Design

Comparison Solutions

Length (m) thickness width (m) Lc t P h k

0.051 0.004 0.229 0.053 0.004 0.465 100.000 53.000

Af Ab At m nf b qt

0.024 0.010 0. 083 30.959 0. 580 1.173 55. 410 583. 892

Length (m) thickness width (m) Lc t P h k

0.051 0.004 0. 229 0.053 0. 004 0.465 100. 000 252. 000

Af Ab At m nf b qt

0.024 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

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Resultsand Discussion: HeatTransfer

Comparison forTypeIII Design

Top Fins (W) Top Fins (W)

Side Fins (W) Side Fins (W)

Total (W) Total (W)

q (W) 245.830

1481.220 1235.390

583.892

651.498

Total Heat Transferred by Aluminum Fins Total Heat Transferred by Steel Fins

679.434

801.786

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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 Electronicsand Causing a Fire

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References

Nematollahi, Khosrow. "Oncourse, ME 450." Scheduled Reading and Assignments.IUPUI. 23 Apr 2007

.

Incropera, Frank, David Dewitt, and Theodore Bergman. Fundamentals of Heat andMass Transfer. 6th. Hoboken NJ: Wilet & Sons, 2007.

Rengifo, Gustavo. "Oncourse, ME 546." ME 546 Resources, Project #1. IUPUI. 23Apr 2007 .

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Questions