Enhancement of sonoluminescence emission from a multibubble cavitation zone

Abstract

Investigations have been performed on various methods of increasing cavitation activity measured by the intensity of sonoluminescence. It is shown that the effect of the combined action of (a) pulsed modulation of an acoustic field, (b) liquid degassing and cooling and (c) increasing the static pressure considerably exceeds the sum of the effects achieved by each of these methods individually. A more than 250-fold increase of the sonoluminescence intensity has been attained compared with continuous irradiation under normal conditions (room temperature, atmospheric pressure, gas-saturated liquid). An interpretation of the results obtained is proposed.

Sonoluminescence and acoustic emission spectra at different stages of cavitation zone development

“…After being kept in the chamber for 24 h, the liquid was subjected to degassing by ultrasound for 20 min at 170 Vpp transducer voltage (≈10 W/cm 2 ). As a result, the air content decreased by 20-25% of the equilibrium value [23]. The preliminary, partial degassing of the liquid considerably increases the reproducibility of the results since, after treatment, the gas content remains practically unchanged under the influence of ultrasound and during the measurements.…”

“…One of the possible ways of avoiding overheating when studying the non-thermal effects of ultrasound on biological cells is to use pulsed ultrasound. In fact, the influence of pulse parameters on cavitation activity has been studied in previous works [19][20][21][22][23]. It has been shown, that pulse duration, pulse period and pulse amplitude affect the size distribution of cavitating bubbles and that the cavitation activity that is estimated, for example by sonoluminescence intensity, can be enhanced in pulsed fields when proper pulse parameters are chosen.…”

Implementation of Effects of Ultrasonic Cavitation Influence as a Factor of Intensification of Extraction of Functional Elements

“…Кавитация -это важный эффект УЗВ, который обусловливает физические и химические изменения в среде воздействия. Механизм ультразвуковой кавитации в жидких системах обусловлен образованием ударных волн, высокой температуры и давления [9,13,12,13,19].…”

Executive Study of Hydrostatic Pressure Effects on Sludge Pretreatment by Sonication

“…On the other hand, a strong effect of hydrostatic pressure on cavitation was found, e.g. optimum pressure of 4.5 atm for a maximum aluminum foil erosion rate [13] or 4 bar for 304L stainless steel corrosion rate [14]. Hydrostatic pressure retards both cavity nucleation (reduction of the total number of cavities) and cavity growth (decrease in the sizes of cavities).…”