Chris Bickford Introduction to Finite Elements HW #5; Problem 2

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Chris Bickford

Introduction to Finite Elements

HW #5; Problem 2

MAPLE:

Using Maple software, the exact solution of the transient response was obtained. The final temperature at the center of the domain u(0.5 , 3600*72) is 45.0697. See the attached Maple sheets for more details.

Part b) ABAQUS FEA CODE:

ABAQUS 6.14 software was used to perform finite element analysis (FEA) to obtain an approximate solution for problem (2). A 2-dimensional transient heat transfer analysis was performed assuming no boundary conditions on the top (x , 0.5) and bottom (x, -

0.5) edges, which effectively makes the problem one-dimensional. Four analyses were performed using two element types (linear and quadratic) and two mesh densities (144

and 288 elements). Figure 1 and Figure 2 show the temperature distribution for the

coarse and fine mesh densities, respectively. Table 1 compares the FEA results with

the exact solution. The results show that both elements performed well at the given mesh densities.

Figure 1 One-Hundred Forty-four (144) Elements: Linear Element Type

Figure 2 Two-Hundred Eighty-eight (288) Elements: Quadratic Element Type

Temperatue at x = 0.5

30

25

20

15

10

5

0

50

45

40

35

0

Linear Elem (144)

Linear Elem (288)

Quadratic Elem (144)

Quadratic Elem (288)

50000 100000 150000

Time

200000 250000

Figure 3 Plot: Time History of Temperature at x = 0.5

Exact Soln

[t = 3600*72]

45.0697

Element

Densities

144

288

Table 1 Final Temperature (t = 3600*72) at x = 0.5

Linear Elements

Value (x=0.5)

44.8471

44.88

% Error

0.49%

0.42%

Quadratic Elements

Value (x=0.5)

44.8911

44.8912

% Error

0.40%

0.40%

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