Aerosol manipulation by acoustic tunable phase-control at resonant frequency

• We propose modular platform of tunable acoustic field for manipulating aerosols.
• Nonuiform acoustic standing wave field at resonant frequency 2.6427 kHz is produced.
• Aerosol manipulation by π-mode phase or 0-mode phase acoustic field is different.
• Effect of aerosol manipulation by π-mode phase is better than that by 0-mode phase.
• The different effects are caused by the structural factors of acoustic field.

The aerosols regularly manipulated by modular platform of acoustic tunable phase-control at resonant frequency 2.6427 kHz are demonstrated in this paper. In order to make full of the superimposition of multiple waves in nonuniform two dimension acoustic standing wave field, the modular platform is composed of the square cavity and the two pairs of symmetric acoustic sources with Helmholtz resonators. The modular platform allows that the effective volume of cavity is 32.8 (length) × 32.8 (width) × 5 (height) cm3 and also the tunable acoustic phase-control is realized by proposed two different phase modes named π-mode phase and 0-mode phase. The ranges of the aerosol size distribution and the aerosol concentration are 0.08 μm–1 μm and 51.6–93.3% (Opacity), respectively. The experimental temperature remains at 298 K. Results indicate that the platform causes perfect nonuniform two-dimension acoustic standing wave field. Under the condition of π-mode phase, the manipulation is better than that under 0-mode phase; the characteristic length of X-pattern for displaying the manipulation is half-wavelength larger than quarter-wavelength acquired in one-dimension acoustic standing wave field. The major areas to remove aerosols are 39 cm2 under π-mode phase and 9.7 cm2 under 0-mode phase. The phase is an important parameter for impacting the manipulation of aerosols. For explaining the difference of manipulation under the two phase conditions, the relative structural factors of acoustic field are found and considered as the intermediate variables from acoustic tunable phase to aerosol manipulation. Especially, the large neck for the shape of sound pressure nodes might cause weak interaction between aerosols and acoustic field and further result in the unexhaustive manipulation.

In this paper, interaction between aerosols and nonuniform two-dimension acoustic standing wave field has been studied in π-mode phase and 0-mode phase at resonant frequency 2.6427 kHz. The study focuses on the effect of tunable phase-control on aerosol manipulation. One of two manipulation effects is showed in the figure.Figure optionsDownload as PowerPoint slide