Outdoor heating, ventilating, and air-conditioning (HVAC) units emit a significant amount
of noise, which may lead to poor sound quality and a perceived low product quality. It is the job
of the noise control engineer to reduce the undesired noise and improve the sound quality of the
outdoor HVAC unit to decrease consumer annoyance. There is great interest in developing a
detailed and accurate acoustic model of the outdoor HVAC unit so that the sound of the outdoor
HVAC unit can be listened to before the unit is constructed. Having an acoustic model which can
synthesize sounds allows the noise control engineer to evaluate and improve the sound quality of
the outdoor HVAC unit during the design process, without the need for extensive prototyping.
Acoustical holography methods will be used to identify and localize noise due to the fan, and other
significant noise sources, to visualize the sound field. In the current study, an acoustic model is
described which can be used to model the noise due to structural radiation and vortex shedding of
the outdoor HVAC unit’s rotating fan blades, one of the top contributors to the unit’s overall noise
level. This moving source model simulates the Doppler effect which occurs when the blade moves
towards and away from a receiver. The results from this moving source model is shown for
different source signals, including sinusoidal, bandpass random, repeating random, and sinusoidal
with time-varying frequency source signals. The parameters of this moving source model will be
optimized to reproduce the experimental results, including the power spectral densities, tonal
power component, and auralizations.