What is the cavitation effect? The cavitation effect means that the high-frequency oscillation signal is converted into high-frequency mechanical oscillation (ultrasound) by the Branson ultrasonic transducer and transmitted to the medium (the cleaning liquid). The radiation of the ultrasonic wave in the cleaning liquid causes the liquid to vibrate. Tens of thousands of tiny bubbles are produced. These bubbles are produced and grown in the negative pressure zone formed by the longitudinal propagation of ultrasonic waves, and quickly close in the positive pressure zone. This is called the cavitation effect.

   There are many other interesting phenomena in the basic effects of cavitation. For example, from the perspective of energy amplification, an ultrasound with a sound pressure amplitude of 0.1MPa can produce sonoluminescence in water. This pressure corresponds to an energy density of approximately 2.2J/cm3, or 4×10-10 eV/molecule (EV is the unit of electron volts, 1eV=1.6021892×10-19J). And Z recently proved that the photons that accompany acousto-luminescence have energy in excess of 6 eV. Therefore, the energy amplification of luminescence produced by sound waves is approximately 1.5×1010. For comparison, consider the case of a thermal neutron causing a fissionable isotope uranium. The neutron has an energy of about 0.025eV, and the energy released by it caused by fission is about 200MeV, then its energy The magnification capacity is only 0.8×1010!

   Another example is a bubble that deforms and vibrates at a rigid interface. Experiments show that in its closed phase, a jet that passes through the center of the bubble, breaks through the bubble wall, and rushes toward the interface is generated. At the same time, it also causes a slight flush of the surrounding liquid.

   From the energy density of the bubble, the bubble quickly closes into the micron-sized bubble, and its density can exceed 1012.Z Near the Los Alamos National Laboratory in the United States for cavitation and micro-fusion (Micro-Fusion) experiments. In heavy water (D2O), there is abnormal heating accompanied by ultrasonic cavitation and 3He and 4He nuclear dust are produced. The reaction rate is 1012-1013Rx/s.

   From the point of view of the cooling rate, after the bubble collapses, the "hot spot" in the bubble cools suddenly, with a cooling rate of 108 K/s. This is equivalent to the rapid cooling rate of molten metal in liquid nitrogen.