WAVES AND VIBRATIONS IN INHOMOGENEOUS STRUCTURES ...

Design variable, t
Design variable, t
Design variable, t
Design variable, t
1.0
0.5
0.0
1.0
0.5
0.0
1.0
0.5
0.0
1.0
0.5
0.0
0.00 0.25 0.50 0.75 1.00
Axial position
0.00 0.25 0.50
Axial position
0.75 1.00
0.00 0.25 0.50 0.75 1.00
Axial position
ARTICLE IN PRESS
J.S. Jensen, N.L. Pedersen / Journal of Sound and Vibration 289 (2006) 967–986 973
0.00 0.25 0.50
Axial position
0.75 1.00
Vel. response (dB)
Vel. response (dB)
Vel. response (dB)
Vel. response (dB)
50
40
30
20
10
0
-10
-20
-30
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Normalized frequency
40
30
20
10
0
-10
-20
-30
-40
-50
0.0 1.0 2.0 3.0 4.0 5.0 6.0
Normalized frequency
40
20
0
-20
-40
-60
-80
-100
-120
-140
-160
0.0 5.0 10.0 15.0 20.0
Normalized frequency
50
0
-50
-100
-150
-200
-250
-300
-350
-400
0.0 10.0 20.0 30.0 40.0 50.0
Normalized frequency
Fig. 2. Optimized design (left) and corresponding velocity response (right) for maximum separation of onþ1 and on.
The material parameters correspond to the ‘elastic rod case’ with m A ¼ 13:21, m B ¼ 2:25. Results are given for four
different values of n, from top to bottom: n ¼ 1; 2; 9; 24.