1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Synchronization of a thermoacoustic oscillator by an external sound source
Rent:
Rent this article for
USD
10.1119/1.4776189
/content/aapt/journal/ajp/81/4/10.1119/1.4776189
http://aip.metastore.ingenta.com/content/aapt/journal/ajp/81/4/10.1119/1.4776189
View: Figures

Figures

Image of Fig. 1.
Fig. 1.

Photographs of (a) the experimental setup and (b) the hot side of the stack. A schematic diagram of the complete experimental setup is shown in (c).

Image of Fig. 2.
Fig. 2.

Arnold tongues obtained in the experiments as a function of the driving frequency f and of the root-mean-square amplitude of the loudspeaker voltage for: (a) d = 5 mm, ds  = 8 cm; (b) d = 5 mm, ds  = 19 cm; and (c) d = 1 mm, ds  = 8 cm. The regions are labelled as follows: PS corresponds to perfect synchronization; QP corresponds to quasi-periodicity (loss of synchronization); IPL corresponds to imperfect phase locking, for which the signal looks quasi-periodic but the phase difference stays bounded; and BD corresponds to “beating death,” for which the self-sustained oscillations are almost reduced to silence.

Image of Fig. 3.
Fig. 3.

Transition to synchronization in the case of weak forcing (  mV): (a) acoustic pressure p(t) and frequency spectra p(f) measured for the two operating points labeled (I) and (II) in Fig. 2(a) ; (b) time evolution of the instantaneous phase difference , and time evolution of the real part of the instantaneous amplitude as a function of its imaginary part in the frame rotating at angular frequency ; (c) normalized amplitude modulation , and normalized time-average phase difference , as functions of the frequency detuning.

Image of Fig. 4.
Fig. 4.

Transition to synchronization in the case of strong forcing ( V): (a) acoustic pressure p(t) and frequency spectra p(f) measured for the three operating points (III), (IV), and (V) in Fig. 2(b) ; (b) time evolution of the instantaneous phase difference and representation in phase space of the operating points (III) to (V); (c) normalized amplitude modulation and normalized time-average phase difference as functions of the frequency detuning.

Image of Fig. 5.
Fig. 5.

Illustration of beating death in the case f = 110 Hz. (a) Measured difference between the sound pressure level due to forcing, and the sound pressure level due to self-sustained oscillations, as a function of the driving voltage . (b) Frequency spectra corresponding to the operating points labeled (VI) and (VII) in Fig. 2(c) . Note that the peaks labeled correspond to measurement “artifacts” related to electromagnetic interference; these peaks are located at the electrical network frequency (50 Hz) and its harmonics, except for a peak at Hz.

Image of Fig. 6.
Fig. 6.

Effect of a feedback loop. (a) Sketch of the experimental setup. (b) Steady-state acoustic pressure as a function of the assigned phase shift between the loudspeaker and the microphone signals, for different values of the voltage gain , where and refer to the voltages at the input and the output of the audio power amplifier, respectively.

Image of Fig. 7.
Fig. 7.

Synchronization in a relaxation regime. The stack position is fixed at ds  = 25 cm while the coupling distance d = 4 cm; the heater power supply Q 0 is fixed at 24.5 W so that a spontaneous and periodic onset/damping of self-sustained oscillations takes place. From the upper graph to the lower graph, the effect of external forcing (frequency f = 176.9 Hz) on the dynamics of wave amplitude evolution is investigated with an increasing loudspeaker voltage . Except for the first (no forcing) and the last graph, the loudspeaker is switched on at time t = 100 s and switched off at time t = 150 s.

Loading

Article metrics loading...

/content/aapt/journal/ajp/81/4/10.1119/1.4776189
2013-03-18
2014-04-18
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Synchronization of a thermoacoustic oscillator by an external sound source
http://aip.metastore.ingenta.com/content/aapt/journal/ajp/81/4/10.1119/1.4776189
10.1119/1.4776189
SEARCH_EXPAND_ITEM