We have been using the method of tube-arrest as a means of producing transient single cavitation bubble. In the present paper we seek to comprehend the mechanism of production and inquire into the structure of the ab ...We have been using the method of tube-arrest as a means of producing transient single cavitation bubble. In the present paper we seek to comprehend the mechanism of production and inquire into the structure of the ab initio pressure field in the arrested liquid column. The generated pressure wave is shown by combining the theoretical analysis with the experimental observation to be a slightly varied version of water hammer. With relatively clean liquid, the magnitude of the tension peak generating the TSB is likely to reach of several millions Pa. It is also shown that the so generated cavitation bubble originating from the gas-containing bulk liquid is in ‘violent’ motion.展开更多
Transmission Loss (TL) of a glass cylinder tube containing a fluid is studied experimentally. This test specimen represents a typical double layer panel including a fluid. The tests are carried out by using a modified...Transmission Loss (TL) of a glass cylinder tube containing a fluid is studied experimentally. This test specimen represents a typical double layer panel including a fluid. The tests are carried out by using a modified four-microphone standing-wave (impedance) tube for specimens with different lengths, 15 and 30 mm. Each cylinder tube is tested filled with one of the fluids at a time. The fluids are air, water, motor oil and a nanoparticle fluid (in absence of magnetic field). The effects of the cylinder length (thickness), impedance tube terminations, and the containing fluid are discussed. The increasing of the thickness led to an increase of the TL values and a decrease in resonance frequencies. Also, the addition of liquid middle layer led to considerable increase of the TL.展开更多
基金supported by the National Natural Science Foundation of China (Grant No 10434070)
文摘We have been using the method of tube-arrest as a means of producing transient single cavitation bubble. In the present paper we seek to comprehend the mechanism of production and inquire into the structure of the ab initio pressure field in the arrested liquid column. The generated pressure wave is shown by combining the theoretical analysis with the experimental observation to be a slightly varied version of water hammer. With relatively clean liquid, the magnitude of the tension peak generating the TSB is likely to reach of several millions Pa. It is also shown that the so generated cavitation bubble originating from the gas-containing bulk liquid is in ‘violent’ motion.
文摘Transmission Loss (TL) of a glass cylinder tube containing a fluid is studied experimentally. This test specimen represents a typical double layer panel including a fluid. The tests are carried out by using a modified four-microphone standing-wave (impedance) tube for specimens with different lengths, 15 and 30 mm. Each cylinder tube is tested filled with one of the fluids at a time. The fluids are air, water, motor oil and a nanoparticle fluid (in absence of magnetic field). The effects of the cylinder length (thickness), impedance tube terminations, and the containing fluid are discussed. The increasing of the thickness led to an increase of the TL values and a decrease in resonance frequencies. Also, the addition of liquid middle layer led to considerable increase of the TL.