Figure 1

(Color online) Experimental setup. C is the container, FG the function generator, Am the amplifier, CA the current conditioner, A the accelerometer, O the oscilloscope, F the interference filter 460 nm, PC the personal computer, DVD the digital video device, and L the lamps. Experiments were conducted under an atmosphere of argon.Reuse & Permissions

Figure 2

Phase diagram of BZ Faraday pattern formation as a function of forcing frequency $f$ and acceleration amplitude $a/g_0$. Continuous lines correspond to the onset of bifurcations predicted for the Faraday instability, where $g^{\left(S1\right)}$ indicates the critical amplitude for the first onset of subharmonic waves, $g^{\left(H\right)}$ is for harmonic waves, and $g^{\left(S2\right)}$ is for the second onset of subharmonic waves. Dashed lines with markers summarize regions with different behaviors observed in the BZ, where $g_1$ indicates the critical amplitude for the onset of vortically filamentary structures, $g_2$ is for advection phase waves, and $g_3$ is for the transition to the homogeneous state. Error bars reflect two facts of important influence in the experiments. On one hand, Faraday patterns are affected by hysteresis. This fact greatly perturbs the critical amplitude $g_2$ as this amplitude depends on the transition from a concentric ring to stripes or rectangles on Faraday waves. On the other hand, bubbles are generated by the BZ reaction, disturbing both Faraday and BZ waves, especially in regions I and II.Reuse & Permissions

Figure 3

Experimental patterns observed in the Belousov-Zhabotinsky reaction forced with the Faraday instability. For the upper panels, region II, the forcing frequency is fixed at 7 Hz, while the amplitude $a/g_0$ changes: 0.6 (A1), 0.8 (A2), and 1.1 (A3), respectively. For the lower panels, region III, as time increases from left to right (7 s between panels), a phase wave ignited at the upper left border spreads over the whole medium ($f=70\text{Hz}$ and $a/g_0=2.5$).Reuse & Permissions

Figure 4

(Color online) Period distribution for a fixed frequency 30 Hz and increasing amplitudes. From left to right: 0, 0.3, 0.4, 0.7, 1.2, 1.7, and 3.0 in units of $g_0$. Graphs show the normalized number of occurrences as a function of the normalized wave period $T/T_b$. For the unforced distributions, periods were measured after 10 min. Labels on top of panels indicate the regions with different behavior observed in the Faraday-BZ system.Reuse & Permissions

Figure 5

(Color online) Mean normalized wave period corresponding to the maximum spectrum of Fig. 4 as a function of the forcing amplitude for constant frequency $f=30\text{Hz}$ in (a) and as a function of the forcing frequency for constant $a/g_0=0.4$ in (b). (b) lies in region I. Dashed lines in (a) coincide with critical amplitudes $g_1$ and $g_2$ separating regions I–III.Reuse & Permissions