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Lumped parameters (acoustic > electrical)
JavaScript calculations can be done below.
The acoustical parameters of the elements can be translated to
electrical parameters. I am using information from Calvert
[2003],
Kinsler ([2000], chapter
8.9 and 10.8) and Colman (pers. comm. [2006]). In the below it is
assumed that
the acoustic circuit is in size
much smaller compared to the
acoustical wavelength and that it is the air.
I am wondering how well the below theoretical model works for
attenuation/resistance, reading
this:
The
attenuation of sound in air due to viscous, thermal and rotational loss
mechanisms is simply proportional to f^{ 2}. However, losses due to vibrational
relaxation of oxygen molecules are generally much greater than those
due to the classical processes, and the attenuation of sound varies
significantly with temperature, watervapour content and frequency.
More study is needed to include at least molecules level attenuation
and influence of humidity. I hope that within the environment of
neolithic buildings these influence are not large (except the humidity
perhaps). Help is needed!
Acoustical inductance of a pipe
L' = ρL/(πa^{2}) [H'] 
Kinsler [2000], formula (10.8.1) and (10.9.5)

with:
ρ = air density:
1.293 [kg/m^{3}] (0°C, 1 atm)
L = effective length of pipe [m]
a = radius of pipe [m^{2}]
Acoustical resistance of a pipe
Thermal and viscous resistance due wall
losses in pipe
Non capillary pipe
R_{w}' = (1.46*L/(πa^{3}))√(4πρηf)
[Ohm'] 
Kinsler [2000], formula (10.8.10) and (10.9.5) 
with:
η = dynamic
viscosity of air, 1.71 x 10^{5} [kg/msec] (0°C, 1 atm)
f = frequency [Hz]
Capillary pipe (Reynolds number is less
than 2000)
R_{wc}'
= 1.46*8ηL/(πa^{4}) [Ohm'] 
Oban [2003],
factor 1.46: Kinsler [2000], formula
(8.9.19) 
Radiation resistance (open segment)
R_{r}' = 2πρf^{2}/c
(flanged) [Ohm'] 
Kinsler [2000], formula (10.8.9) and (10.9.5) 
R_{r}' = πρf^{2}/c
(unflanged) [Ohm'] 
Kinsler [2000], formula (10.8.9) and (10.9.5) 
Acoustical capacitance of rigid
container/cavity
C' = V/(ρc^{2})^{ }[F'] 
Kinsler [2000], formula (10.8.4) and (10.9.5) 
with:
c = sound speed in air:
331.5 [m/sec] (0°C, 1 atm)
V = volume of container [m^{3}]
Thermal resistance in container
R_{ct}' = ρc^{2}/(0.46*√(πηf/ρ)*A)
[Ohm'] 
Coltman,
pers. comm [2006]

with:
A = area of cylinder with radius a and length 2*a, where a is such that
the cylinder has volume V
Helmholtz resonator
Frequency
f_{helm} = 1/(2π√(L'C'))
[Hz] 
Calvert [2003] 
Quality factor
Q_{helm} = 2πf_{helm}L'*(
1/(R_{w}'_{(fhelm)}+
R_{r}'_{(fhelm)})+1/R_{ct}')
[] 

Calculations
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As example a
Florence flask is used.
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