Research Article

The Technique of MIEELDLD in Computational Aeroacoustics

Table 5

Comparing the dispersive and group velocity properties for two spatial methods BOGEY and BOGEY-NEW in terms of number of points per wavelength (to 4 d.p).

Accuracy Method Max. value of 𝜃 No. of pts per wavelength

| 𝜃 𝜃 | 𝜋 5 × 1 0 3 BOGEY 1.4875 4.2240
| 𝜃 𝜃 | 𝜋 5 × 1 0 3 BOGEY-NEW 1.5175 4.1405
| 𝜃 𝜃 | 𝜋 5 × 1 0 4 BOGEY 1.6529 3.8013
| 𝜃 𝜃 | 𝜋 5 × 1 0 4 BOGEY-NEW 1.6733 3.7550
| | | | 𝑑 𝑑 ( 𝜃 ) ( 𝜃 | | | | ) 1 . 0 5 × 1 0 3 BOGEY 1.0572 5.9433
| | | | 𝑑 𝑑 ( 𝜃 ) ( 𝜃 | | | | ) 1 . 0 5 × 1 0 3 BOGEY-NEW 1.0523 5.9710
| | | | 𝑑 𝑑 ( 𝜃 ) ( 𝜃 | | | | ) 1 . 0 5 × 1 0 4 BOGEY 0.8784 7.1533
| | | | 𝑑 𝑑 ( 𝜃 ) ( 𝜃 | | | | ) 1 . 0 5 × 1 0 4 BOGEY-NEW 0.9049 6.9437