.
( )
.
1)
ASHARAE
ASHARAE
.
/
200mm 2800mm
1.2mm 1800mm×1800mm
24mm
1.7m 1.0m
/
0.5m 1.0m
2)
Study On End Reflection Loss of Duct
Prat2.In the case of using the End Reflection Loss energy value Maya SATOH Hiroyoshi SHIOKAWA
× Hz m
(Hz √ (m
D
dB
−日本大学生産工学部第43回学術講演会（2010-12-4）−
― 63 ―
4-17
0s 1.5ms
7.9ms 9.4ms
16.6ms 18.1ms
4.6ms 21.2ms
0
Ii
Ir It
Ibi
Ibr
( )Ibt L
IbtL
IbiL
IbtL
Ibi⊿L ( )
Ⅰ
Ibt
=Ibi Ibr
[W/ ]
⊿L
=L
IbiL
Ibt [dB]Ibi
B[W/ ]
Ibr
B[W/ ]
L
Ibi B[dB]
6ms 6ms
(ms)
(ms)
(ms) 0
0 0
5
5 5
10
20 10
10
15 15 15
20 20
― 64 ―
L
Ibt B[dB]
L
Ibi( )
L
wbiIct L
Ict0.5m
( )
L
wctL
wctL
wbi⊿L ( )
0.5m Ⅱ(50) 1.0m
Ⅱ(100)
L
wbi=L
Ibi 10log10S
[dB]L
wct=L
Ict 20log10r
11 [dB]⊿L
=L
wbiL
wct [dB]L
wbi B [dB]L
Ibi B [dB]L
wct C[dB]
L
Ict C[dB]
S
[ ]r
[ ].
50
1500Hz Ⅰ
200mmφ ASHRAE
ASHRAE 100 250Hz
1.9dB
250Hz 450 Hz 1.1dB 450 Hz
0.6 dB
50
1500Hz Ⅱ(50)
Ⅱ(100) 200mmφ
ASHRAE
Ⅱ(50) Ⅱ(100)
ASHRAE 50Hz
250 Hz 1.0dB
500Hz
ASHRAE
(50) (100)
ASHRAE
ASHRAE .
50
1500Hz Ⅰ
200mmφ ASHRAE
ASHRAE 100
250Hz 1.6dB
250 Hz 0.6 dB
ASHRAE 20
50 100 500 1000
50 100 500 1000 15
10
5
0
(50)
(100)
ASHRAE 20
15
10 25
5 0
(Hz) (Hz)
dBdBdB
50 100 500 1000 (Hz)
ASHRAE 20
15
10
5 0
― 65 ―
50
1500Hz Ⅱ(50)
Ⅱ(100) 200mmφ
ASHRAE
Ⅱ(50) Ⅱ(100)
ASHRAE 50Hz
250 Hz 1.3dB
350Hz
.
250Hz Ⅰ 250Hz
Ⅱ
200mmφ ASHRAE
ASHRAE 1.1dB
1
100 250Hz ASHRAE 250 450 Hz
1.2dB 450 Hz
100 250Hz
ASHRAE 250Hz
2
0.5m 1.0m
50
250Hz ASHRAE 1.3dB
ASHRAE
3 200mm
250Hz
Ⅰ 250Hz Ⅱ
50 1500Hz ASHRAE
(50) (100)
ASHRAE
200mmφ ASHRAE
1)
pp.119-120 2009.12 2)
pp.40 2007.3
(50)
(100)
ASHRAE
( )
( )
ASHRAE ( )
ASHRAE ( )
50 100 500 1000
50 100 500 1000 (Hz)
(Hz) 20
10 15 25 20
15
5 10
0 5
dBdB
0
