(C) IDM Energiesysteme GmbH
5. General description
Installation instructions AERO ILM
22
Installation
Major factors of in
fl
uence are:
• sound attenuation by massive barriers e.g. buil-
dings, walls or di
ff
erent terrain.
• re
fl
ection on acoustically hard ground e.g. glass
facade and stone surfaces
• attenuation due to sound absorbing porous sur-
faces e.g. grass, trees
• reinforcement/reduction of by wind speed/direction
Noise-Immission
The noise caused by an source at a certain place is
expressed as Immission, the corresponding sound
pressure level is called Immission level.The immissi-
on level at the relevant place of immission can either
be determined by measurements or calculation e.g.
forecasting method according „TA Lärm“ (German
Noise Prevention Code) especially, which is espe-
cially useful at the stage of planning.
According to this method of calculation, the expected
sound pressure level is calculated on the basis of the
sound power level of the heat pump, the distance
of the heat pump to the receiver location and the
installation situation (directivity correction Dc) of the
relevant place of immission according the following
formula:
2: Spherical spreading into 1/4 space
1: Spherical spreading into 1/2 space
3: Spherical spreading into 1/8 space:
L
WAeq
= mean A-weighted sound pressure level [dB]
D
C
= directionality correction [-]
S
m
= distance from noise source to receiver
location [m]
The following
fi
gures show the di
ff
erent installation
situations of heat pumps and the corresponding di-
rectivity correction.
