Panasonic WH-SDF03E3E5 Series Design Handbook page 87

Sound
propagation
Q =
Arrangement
Directional factor Q for different arrangements of the sound source
Aquarea air / water heat pump – design handbook 07 / 2014
• Interruption by obstructions like buildings, walls or landscape
formations
• Reflection from surfaces such as walls, glass facades, buildings or
asphalt-covered areas as well as areas made of stone
• Absorption of sound on e.g. grass, bark-chip mulch, leaves or
fresh-fallen snow
• Wind can increase or decrease the sound pressure level (depending
on wind direction).
An estimation of the sound pressure level L
a distance r from the heat pump can be calculated with the following
formula based on the sound power level L
L = L
Aeq WAeq
For this, one additionally needs the direction factor Q, which considers
the spatial radiation conditions of the sound source:
Half space
2
Q
( )
+ 10 × log
4 × π × r²
Quarter space
4
Project Design
Acoustics
Sound power level
at a certain place with
Aeq
:
WAeq
Eighth space
8
87