Fan with reduced noise generation
US6872048B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 2001 |
| Grant date | Mar 29, 2005 |
| Priority date | — |
| Expiry date | May 26, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S416/03
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Axial flow fan propellers are provided with a roughened portion along the trailing edge of the fan blades on the pressure side of the blade to minimize tonal acoustic emissions generated by laminar boundary layer vortex shedding. The roughened portion may be provided by trip surfaces formed in the blades, by strips of abrasive material adhered to the blades along the trailing edges, respectively, by parallel or cross-hatched serrations in the blades or by upturned or offset trailing edges of the blades. The height of the roughened portion should be about equal to the boundary layer thickness of air flowing over the blade surfaces during operation of the fan. The fan propellers are particularly advantageous in heat exchanger applications, such as residential air conditioning system condenser units.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.