Design of a Replacement Condenser Fan for Reduced Noise and Improved Sound Quality 2008-36-0549
The design and development of a condenser fan for a transport refrigeration unit is described. Several sound-producing flow features were present with the original fan, causing it to be the dominant sound source in some operating modes of this diesel-powered unit. These features included upstream wakes and disturbances, blade tip vortex interaction, and circumferential non-uniformities. The development of the design features of the new fan which are used to suppress noise caused by interaction with these flow features is described. The replacement fan produces similar flow, while being 7 dBA quieter overall with improved sound quality.