Dynamics of Machines - Part II - IFS.pdf

1.6.12 Resonance – Experimental Analysis in Time Domain
(a) Amplitude [m/s 2 ]
(b) Amplitude [m/s 2 ]
3
2
1
0
−1
−2
−3
x 10 −5 Signal (a) in Time Domain − (b) in Frequency Domain
0 5 10 15
time [s]
20 25 30
x 10−5
1.5
1
0.5
0
0 5 10 15 20 25
frequency [Hz]
(a) Amplitude [m/s 2 ]
(b) Amplitude [m/s 2 ]
(a) Amplitude [m/s 2 ]
(b) Amplitude [m/s 2 ]
3
2
1
0
−1
−2
−3
0.5
x 10 −5 Signal (a) in Time Domain − (b) in Frequency Domain
0 5 10 15
time [s]
20 25 30
x 10−5
1.5
1
0
0 5 10 15 20 25
frequency [Hz]
3
2
1
0
−1
−2
−3
0.5
x 10 −5 Signal (a) in Time Domain − (b) in Frequency Domain
0 5 10 15
time [s]
20 25 30
x 10−5
1.5
1
0
0 5 10 15 20 25
frequency [Hz]
Figure 20: Resonance phenomena due to force excitations with frequency around the natural
frequency of the mass-spring system: 1 D.O.F. system with natural frequency of 0.87 Hz, excited
by the shaker with frequencies of 0.80 Hz, 0.87 Hz and 0.90 Hz – Spring-mass system (A) with
two masses m = m1 + m2 = 0.382 Kg fixed at the beam (A) length L1 = 0.600 m, resulting in a
natural frequency of 0.87 Hz.
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