M S V National Taiwan Ocean University MSVLAB

M S V National Taiwan Ocean University MSVLAB (海大河 系) Department of Harbor and River Engineering Fictitious frequencies in the null-field BIEM Wei-Ming Lee 1, Jeng-Tzong Chen 2 Ying-Te Lee 1, 1 Department of Mechanical Engineering, China Institute of Technology, Taipei, Taiwan 2 Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung, Taiwan 2009年 06月26日 0

M S Case 1: An infinite plate with one hole V Geometric data: a =1 m thickness=0. 002 m Boundary condition: Inner edge : free 1

M S Flexural wave of plate with one hole (Lee W M) V 2

M S Case 2: An infinite plate with two holes V 3

M S Flexural wave of plate with two holes (Lee W M) V 4

M S V Fictitious frequencies in BEM (JSV, 1990 Dokumci E) Imag. -part Real. -part (JSV, 1994 P Juhl) 5

M S V Fictitious frequencies in BEM (JSV, 1990 Dokumci E, BEM using circulant) Imag. -part Real. -part (Null-field BIEM using Fourier base) 6

M S Five cases of fictitious frequencies V 1. Flexural wave of plate with one hole and two holes (W M Lee) 2. One and two spheres radiation and scattering (Y T Lee) 3. One and two cylinders scattering of water wave (Y T Lee) 4. One and two cylinders scattering of acoustics (Y C Lin) 5. JSV (Dokumaci E and Juhl, P) 7