The paper considers receiving acoustic horns designed for particle velocity amplification and suitable for use in vector sensing applications. Unlike conventional horns, designed for acoustic pressure amplification, acoustic velocity horns (AVHs) deliver significant velocity amplification even when the overall size of the horn is much less than an acoustic wavelength. An AVH requires an open-en...

The particle size distribution of pulverized fuel in pneumatic conveying pipelines is an important physical characteristic closely related to mill energy economy, fuel flow property, combustion efficiency and pollutant emissions. In order to determine the size distribution of pneumatically conveyed fuel particles on an online continuous basis, an instrumentation system based on acoustic emissio...

We present an experimental study of velocity statistics for a partial layer of inelastic colliding beads driven by a vertically oscillating boundary. Over a wide range of parameters (accelerations 3-8 times the gravitational acceleration), the probability distribution P (v) deviates measurably from a Gaus-sian for the two horizontal velocity components. It can be described by P (v) ∼ exp(−|v/v ...

Particle inhalation from the ambient environment and particle deposition in the respiratory tracts are numerically investigated using an integrated breathing human manikin which includes detailed facial features as well as nasal cavity, laryngopharynx and trachea. Visualized and quantitative results including the airflow field, particle tracks and particle inhalation and deposition patterns are...

We present an experimental study of velocity statistics for a partial layer of inelastic colliding beads driven by a vertically oscillating boundary. Over a wide range of parameters (accelerations 3-8 times the gravitational acceleration), the probability distribution P (v) deviates measurably from a Gaus-sian for the two horizontal velocity components. It can be described by P (v) ∼ exp(−|v/v ...