Improved acoustic impedance tube

Cross-sectional area

A

94 × 94 mm²

Volume flow rate

Q

0 - 100 ℓ/min

Thickness of background air space

L

35, 50, 62, and 73 mm

Tube length without perforated plate

L₁

710 mm

Regulator pressure

p

0.15, 0.20, and 0.25 MPa

Perforated plate

Plate thickness

t

1, and 3 mm

Number of micropores

N

64

Diameter of micropores

d

2 mm

Opening ratio of micropores

σ

2.28%