Design of terminating ducts for fan noise testing

摘要

This paper falls within the framework of the ISO 13347 draft for acoustical fan testing. The purpose of this standard is to define laboratory condition test methods for the determination of fan sound power levels radiated by free inlet, free outlet and fan casing. the project describes three test methods adapted to fans which draw on general acoustic standards ISO 3743, ISO 3744 and ISO 9614 namely, the Reverberant Room Method, the Enveloping Surface Method an the Sound Intensity Method. In parallel with this project, ISO 5136 details the procedure for measuring the sound in -duct power of ducted fans (1).