Demonstration comparing sound wave attenuation inside pipes containing bubbly water and water droplet fog

Abstract

This paper describes a demonstration and explanation of sound absorption in water due to bubbles, and in air due to a fog of water droplets. It is suitable for 10-12 year olds, but the paper indicates where further exploration of the simplifications in the explanations provided for that age range would allow the demonstration to be used for undergraduate and Masters-level teaching. Applications to submarines, the space shuttle, and neutron generators are described. The demonstration is designed for transportation in a family-sized car.

Investigation of a method for real time quantification of gas bubbles in pipelines

“…Such a peaked population was previously measured using an optical method 10 in this pipe after gas injection through a vibrated needle. 28,29 Note that the unit (bin size) of n b R 0 ð Þ is not critical in the calculation of Eqs. (3)- (5) the contribution of each bubble to the EIV is modeled as proportional to R l 0 , where the above-mentioned quadratic dependence corresponds to l ¼ 2, while the value l ¼ 1 would be the case where a bubble's EIV is linearly dependent on bubble radius.…”

“…For any given void fraction, the relative numbers of small and large bubbles can be altered by use of a mobile phone vibrator placed on the needle. 28,29 The sensor pair is mounted face to face across the tube about 1.5 m from the bottom. The transmitter is driven by a signal generator and the signal collected by a receiver is recorded by a DAQ system.…”

Reflection of acoustic waves from the boundary or layer of two-phase medium

“…The problem of small disturbance propagation in a liquid with gas-vapor bubbles in some or another formulation was studied in [20][21][22][23][24][25][26][27][28][29][30][31][32][33].…”

Propagación del sonido en exteriores en condiciones de niebla

“…A la hora de validar los modelos mencionados lo han sido comparando lo predicho teóricamente con datos experimentales obtenidos en medios donde la niebla era simulada y en un espacio cerrado [22] [23] o bien, en otras ocasiones, los valores acústicos eran medidos dentro de un tubo donde las características físicas de las gotas de líquido en suspensión en el medio de transmisión del sonido eran controladas [24] [25].…”

“…Sea como fuere, habiéndose conocido antes o después, los nombres de Isaac Newton y de Samuel Pepys quedarán indisolublemente unidos para la historia en la portada de la primera edición del Principia [35] 24 -publicada en julio de 1686-en la que aparece el nombre de Pepys como editor, ya que Pepys ostentaba en esas fechas la presidencia de la Royal Society 25 .…”