Table 1 Fractals CMPPs metamaterials parameters and its acoustic absorption behavior of a unit cell.

1

A1

\({\varnothing }_{1}\) = 7.07%, \({\varnothing }_{2}\) = 12.56%

@950 Hz (α > 91%)

58

2

A2

\({\varnothing }_{1}\) = 19.63%, \({\varnothing }_{2}\) = 28.26%

@1200 Hz (α > 90%)

45

3

A3

\({\varnothing }_{1}\) = 38.46%, \({\varnothing }_{2}\) = 50.24%

@1300 Hz (α > 91%)

50

4

A4

\({\varnothing }_{1}\) = 63.59%, \({\varnothing }_{2}\) = 78.5%

@1450 (α > 65%)

40

5

A5

\({\varnothing }_{1}\) = 7.07%, \({\varnothing }_{2}\) = 19.63%

@1000 Hz (α > 95%)

60

6

A6

\({\varnothing }_{1}\) = 7.07%, \({\varnothing }_{2}\) = 50.24%

@800 Hz (α > 81%)

37.5

7

A7

\({\varnothing }_{1}\) = 19.63%, \({\varnothing }_{2}\) = 50.24%

@1000 Hz (α > 98%)

25

8

A8

\({\varnothing }_{1}\) = 38.46%, \({\varnothing }_{2}\) = 78.5%

@1200 Hz (α > 40%)

0