Cylindrical acoustic levitator/concentrator having non-circular cross-section
US6644118B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 2002 |
| Grant date | Nov 11, 2003 |
| Priority date | — |
| Expiry date | Sep 13, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D49/006
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A low-power, inexpensive acoustic apparatus for levitation and/or concentration of aerosols and small liquid/solid samples having particulates up to several millimeters in diameter in air or other fluids is described. It is constructed from a commercially available, hollow piezoelectric crystal which has been formed with a cylindrical cross-section to tune the resonance frequency of the breathing mode resonance of the crystal to that of the interior cavity of the cylinder. When the resonance frequency of the interior cylindrical cavity is matched to the breathing mode resonance of the cylindrical piezoelectric transducer, the acoustic efficiency for establishing a standing wave pattern in the cavity is high. By deforming the circular cross-section of the transducer, the acoustic force is concentrated along axial regions parallel to the axis of the transducer. The cylinder does not require accurate alignment of a resonant cavity. The concentrated regions of acoustic force cause particles in the fluid to concentrate within the regions of acoustic force for separation from the fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.