1. Figure 1 Schematic Representation of a Hole𝑦
𝑝 𝑟
𝑝 𝑖
𝑝 𝑠
𝑍 𝑟1
𝑝 1
𝑢 1 𝑥
𝑝 𝑖1
𝑝 𝑖2
𝑝 2
𝑢 2
𝑝 𝑡
𝑍 𝑟2 𝑧
Figure 1 Schematic Representation of a Hole

2. Figure 1 Schematic Representation of a Hole

3. Figure 2 Schematic Conical Hole𝐿
𝑙 1
𝑙 2
𝑟 2
𝑆 2
𝑟 1
𝑆 1
Figure 2 Schematic Conical Hole

4. Figure 2 Schematic Conical Hole

5. Radiation Impedance
Diffuse Acoustic Field
Figure 3 VA-One Model

6. Radiation Impedance
Diffuse Acoustic Field
Figure 3 VA-One Model

7. Figure 4 Comparsion of Results of a Hole (𝑅=5.64𝑚𝑚, 𝐿=100𝑚𝑚)

8. Figure 5 Effect of Hole Shape

9. Figure 6 Results of Conical Hole

10. Figure 7 Effect of Radius Ratio of Conical Hole

11. 𝑟 𝑅
𝑙 2
𝑙 1
Figure 8 Dimensions of Hole with Area Change

13. Figure 9 Effect of Radius Change of Straight Hole

14. 𝑟 3
𝑟 1
𝑟 2
𝑙 3
𝑙 2
𝑙 1
Figure 10 Dimensions of Hole with Expansion

16. Figure 11 Results of Hole with Expansion Chamber

17. Figure 12 Comparison the Effect of Different Cross Area of Hole with Expansion Chamber

18. Figure 13 Comparison of Length Effect of Hole with Expansion Chamber

19. 𝑉 𝑐
𝐴 1 𝐵 1 𝐶 1 𝐷 1
𝐴 2 𝐵 2 𝐶 2 𝐷 2
𝑅 𝑛
𝑙 𝑛
Figure 14 Schematic Representation of Hole with Helmholtz Resonator ( 𝑙 𝑛 =10𝑚𝑚, 𝑅 𝑛 =5.64𝑚𝑚, 𝑉 𝑐 =12𝑐 𝑚 3 )

21. Figure 15 Comparison of Results of Hole with Helmholtz Resonator

22. Figure 16 Comparison of Results of Large Opening