This study investigates reliable models and methods to be applied in sound field analysis of multi-domain structures. The case structures are two monuments, namely, Süleymaniye Mosque and Hagia Sophia in İstanbul. These are both multi-volume spaces with many smaller sub-volumes coupled to each other by coupling apertures in form of arches. A key concern of the study is to examine energy flow decays and understand the mechanism of multi-slope sound energy decays. The methodology involves diffusion equation model (DEM) application in a finite-element scheme for sound energy flow analysis. Energy flow decays, energy flow dips, and spatial flow vectors are examined for single versus multi-domain DEM solutions. It is concluded that specification of different domains with individual diffusion coefficients is a critical setting such that, if not assigned correctly, may mislead the results. The energy flow vector analysis has enabled us to comprehend the architectural features in relation to such energy flow decay dip occurrence. The computational efficiency of DEM is also discussed. The DEM application in this study has proved to be a powerful and practical method in room acoustics applications, specifically for multi-rate decay investigations.

1.
G. M.
Naylor
, “
Odeon—Another hybrid room acoustical model
,”
Appl. Acoust.
38
,
131
143
(
1993
).
2.
J. H.
Rindel
, “
The use of computer modeling in room acoustics
,”
J. Vibroeng.
3
,
219
224
(
2000
).
3.
C. F.
Eyring
, “
Reverberation time measurements in coupled rooms
,”
J. Acoust. Soc. Am.
3
,
181
206
(
1931
).
4.
L.
Cremer
and
H. A.
Müller
, “
Coupled rooms
,” in
Principles and Applications of Room Acoustics
(
Elsevier
,
London
,
1978
), Vol. 1, pp.
261
292
.
5.
E. N.
Wester
and
B. R.
Mace
, “
A statistical analysis of acoustical energy flow in two coupled rectangular rooms
,”
Acta Acust.
84
,
114
121
(
1998
).
6.
J. S.
Anderson
and
M. B.
Anderson
, “
Acoustic coupling effects in St Paul's Cathedral, London
,”
J. Sound Vib.
236
,
209
225
(
2000
).
7.
F.
Martellotta
, “
Identifying acoustical coupling by measurements and prediction-models for St. Peter's Basilica in Rome
,”
J. Acoust. Soc. Am.
126
,
1175
1186
(
2009
).
8.
A.
Billon
,
V.
Valeau
,
A.
Sakout
, and
J.
Picaut
, “
On the use of a diffusion model for acoustically coupled rooms
,”
J. Acoust. Soc. Am.
120
,
2043
2054
(
2006
).
9.
N.
Xiang
,
Y.
Jing
, and
A. C.
Bockman
, “
Investigation of acoustically coupled enclosures using a diffusion-equation model
,”
J. Acoust. Soc. Am.
126
,
1187
1198
(
2009
).
10.
P.
Luizard
,
J. D.
Polack
, and
B. F. G.
Katz
, “
Sound energy decay in coupled spaces using a parametric analytical solution of a diffusion equation
,”
J. Acoust. Soc. Am.
135
,
2765
2776
(
2014
).
11.
Z.
Su Gul
,
N.
Xiang
, and
M.
Caliskan
, “
Investigations on sound energy decays and flows in a monumental mosque
,”
J. Acoust. Soc. Am.
140
,
344
355
(
2016
).
12.
Z.
Su Gul
,
N.
Xiang
, and
M.
Caliskan
, “
Diffusion equation based finite element modeling of a monumental worship space
,”
J. Comput. Acoust.
25
,
1
16
(
2017
).
13.
C. M.
Harris
and
H.
Feshbach
, “
On the acoustics of coupled rooms
,”
J. Acoust. Soc. Am.
22
,
572
578
(
1950
).
14.
M.
Meissner
, “
Computational studies of steady-state sound field and reverberant sound decay in a system of two coupled rooms
,”
Open Phys.
5
,
293
312
(
2007
).
15.
L.
Nijs
,
G.
Jansens
,
G.
Vermeir
, and
M.
Voorden
, “
Absorbing surfaces in ray-tracing programs for coupled spaces
,”
Appl. Acoust.
63
,
611
626
(
2002
).
16.
J. E.
Summers
,
R. R.
Torres
, and
Y.
Shimizu
, “
Statistical-acoustics models of energy decay in systems of coupled rooms and their relation to geometrical acoustics
,”
J. Acoust. Soc. Am.
116
,
958
969
(
2004
).
17.
J. E.
Summers
,
R. R.
Torres
,
Y.
Shimizu
, and
B. L.
Dalenback
, “
Adapting a randomized beam-axis tracing algorithm to modeling of coupled rooms via late-part ray tracing
,”
J. Acoust. Soc. Am.
118
,
1491
1502
(
2005
).
18.
A. C.
Raes
and
G. G.
Sacerdote
, “
Measurements of the acoustical properties of two Roman basilicas
,”
J. Acoust. Soc. Am.
25
,
954
961
(
1953
).
19.
F.
Martellotta1
,
L Álvarez-Morales, S. Girón, and T. Zamarreño, “An investigation of multi-rate sound decay under strongly non-diffuse conditions: The Crypt of the Cathedral of Cadiz
,”
J. Sound Vib.
421
,
261
274
(
2018
).
20.
Z.
Su Gul
,
M.
Caliskan
,
A.
Tavukcuoglu
, and
N.
Xiang
, “
Assessment of acoustical indicators in multi-domed historic structures by non-exponential energy decay analysis
,”
Acoust. Aust.
46
,
181
192
(
2018
).
21.
N.
Xiang
,
P. M.
Goggans
,
T.
Jasa
, and
P.
Robinson
, “
Bayesian characterization of multiple-slope sound energy decays in coupled-volume systems
,”
J. Acoust. Soc. Am.
129
,
741
752
(
2011
).
22.
N.
Xiang
and
P. M.
Goggans
, “
Evaluation of decay times in coupled spaces: Bayesian parameter estimation
,”
J. Acoust. Soc. Am.
110
,
1415
1424
(
2001
).
23.
D. A.
Kuban
, “
Symbol of Ottoman architecture: The Süleymaniye
,” in
Ottoman Architecture
(
Antique Collectors' Club
,
Suffolk, UK
,
2010
), pp.
277
294
.
24.
Süleymaniye Mosque Documents (T. R. Prime Ministry Directorate General of Foundations Archive, Ankara, Turkey,
2011
).
25.
G.
Necipoglu-Kafadar
, “
The Süleymaniye Complex in İstanbul: An interpretation
,”
Muqarnas
3
,
92
117
(
1985
).
26.
H.
Kahler
and
C.
Mango
,
Hagia Sophia
(
Frederick A. Praeger
,
New York
,
1967
),
p. 250
.
27.
W. E.
Klenbauer
,
A.
White
, and
H.
Matthews
,
Hagia Sophia
(
Scala Publishers
,
London
,
2004
).
28.
Z.
Su Gul
,
M.
Caliskan
, and
A.
Tavukcuoglu
, “
On the acoustics of Süleymaniye Mosque: From past to present
,”
Megaron
9
,
201
216
(
2014
).
29.
F.
Ollendorff
, “
Statistical room-acoustics as a problem of diffusion: A proposal
,”
Acustica
21
,
236
245
(
1969
).
30.
J. M.
Navarro
,
F.
Jacobsen
,
J.
Escolano
, and
J. J.
López
, “
A theoretical approach to room acoustic simulations based on a radiative transfer model
,”
Acta Acust. united Acust.
96
,
1078
1089
(
2010
).
31.
J.
Picaut
,
L.
Simon
, and
J. D.
Polack
, “
A mathematical model of diffuse sound field based on a diffusion equation
,”
Acta Acust.
83
,
614
621
(
1997
).
32.
C.
Visentin
,
N.
Prodi
,
V.
Valeau
, and
J.
Picaut
, “
A numerical investigation of the Fick's law of diffusion in room acoustics
,”
J. Acoust. Soc. Am.
132
,
3180
3189
(
2012
).
33.
V.
Valeau
,
J.
Picaut
, and
M.
Hodgson
, “
On the use of a diffusion equation for room-acoustic prediction
,”
J. Acoust. Soc. Am.
119
,
1504
1513
(
2006
).
34.
Y.
Jing
and
N.
Xiang
, “
On boundary conditions for the diffusion equation in room acoustic prediction: Theory, simulations, and experiments
,”
J. Acoust. Soc. Am.
123
,
145
153
(
2008
).
35.
Y.
Jing
and
N.
Xiang
, “
Visualizations of sound energy across coupled rooms using a diffusion equation model
,”
J. Acoust. Soc. Am.
124
,
EL360
EL365
(
2008
).
36.
N.
Xiang
,
J.
Escolano
,
J. M.
Navarro
, and
Y.
Jing
, “
Investigation on the effect of aperture sizes and receiver positions in coupled rooms
,”
J. Acoust. Soc. Am.
133
,
3975
3985
(
2013
).
37.
J. M.
Navarro
,
J.
Escolano
,
M.
Cobos
, and
J. J.
Lopez
, “
Influence of the scattering and absorption coefficients on homogeneous room simulations that use a diffusion equation model
,”
J. Acoust. Soc. Am.
133
,
EL1218
EL1221
(
2013
).
You do not currently have access to this content.