| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve sound absorption and scattering efficiency per unit area on a side face of pipes forming an acoustic structure. <P>SOLUTION: An acoustic structure 10 includes: first type pipes 1-1 to 1-3 with a length of D11, a width of W11, and a height of H11; second type pipes 1-4 and 1-5 with a length of D12 (D12<D11), a width of W12 (W12<W11), and a height of H12 (H12=H11); and third type pipes 1-6 and 1-7 with a length of D13 (D13=D11-D12<D12), a width of W13 (W13=W12<W11), and a height of H13 (H13=H11). Openings 2-1 to 2-7 are provided on a side face CU of pipes 1-1 to 1-7. <P>COPYRIGHT: (C)2013,JPO&INPIT |
