Stable sonoluminescence within a water hammer tube

Abstract

The sonoluminescence (SL) from the collapse of a single gas bubble within a liquid can be produced repetitively using an acoustic resonator. An alternative technique using a water hammer tube, producing SL from bubbles of greater size, is described here. A sealed vertical tube partly filled with a liquid and a gas at low pressure is subjected to vertical vibrations. The oscillation of the pressure within the liquid column, due to inertial forces, excites cavitation bubbles to grow and collapse. Rotation is used to confine the bubbles to the axis of the tube. Bright SL emissions were observed in a number of liquids. Repetitive emission was produced from bubbles in condensed phosphoric acid. Bubbles of 0.4 mm ambient radius (containing 2x 10(14) xenon atoms) were excited by vibration at 35 Hz. Approximately 10(12) photons were emitted per collapse in the range 400-700 nm (over four orders of magnitude greater than the brightest SL reported previously), corresponding to a 1% efficiency of the conversion of mechanical energy into light.

Molecular and atomic emission during single- bubble cavitation in concentrated sulfuric acid

“…Note that atomic Xe emission has been previously reported from bubble compression in phosphoric acid (H 3 PO 4 ) by a tube-arrest (''water hammer'') method. 10 The Xe and Ar spectra also show very broad peaks in the near-UV region of the spectra with the peak in the Ar spectrum blueshifted relative to the peak in the Xe spectrum. This has also been reported for SBSL from pure water.…”

Sonoluminescence and dynamics of cavitation bubble populations in sulfuric acid

“…Due to their high emission power, noble gas bubbles in acids are ideal candidates for sonoluminescence studies, and the literature on such experiments is continuously growing. For SL in H 2 SO 4 , see for instance [8,9,10,11,12,13,14,15,16,18,17,19,20,21,22,23,24,25,26,27]. The basic mechanism of light emission in the acids is believed to be similar to that observed in other liquids like water (see e.g.…”

Water hammer with column separation: A historical review

“…In particular, the occurrence of column separation may have a significant impact on subsequent transients in the system. Column separation is like the breaking of a solid rod or rope-Galilei already described this analogy (Rouse andInce, 1957, 1963, p. 57)-and the phenomenon can be nicely demonstrated in a simple toy apparatus (Wylie, 1999) that emits light flashes when filled with glycerin (Schmid, 1959;Chakravarty et al, 2004). Large pressures with steep wave fronts may occur when column separations collapse and the practical implications are therefore significant.…”

“…Su et al (2003) observed the strongest light signals when water with xenon was cooled to near its freezing point. Chakravarty et al (2004) conducted tests with many different liquids. They found the best cavitation sonoluminescence in liquids with a low vapor pressure and a moderately high viscosity.…”