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Table 4.

Configuration of the airflow resistivity of each layer for materials with different gradient structures.

Layer 1 Airflow resistivity (N⋅s/m4) Layer 2 Airflow resistivity (N⋅s/m4)
Low-to-high resistivity gradient structures 11 600 21 600
11 600 31 600
11 600 41 600
High-to-low resistivity gradient structures 21 600 11 600
31 600 11 600
41 600 11 600

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