Skip to main content

Theory and Modern Applications

Table 1 The number of multigrid V-cycles with two schemes and different values of \(\pmb{k=10,50, 100,500,1\text{,}000}\) and \(\pmb{\lambda=-0.9}\) for Example 1 , where \(\pmb{e^{-5}=10^{-5}}\)

From: Multigrid method based on transformation-free high-order scheme for solving 2D Helmholtz equation on nonuniform grids

 

k

N  = 16

N  = 32

N  = 64

N  = 128

CDS

10

\(3.4623e^{-5}\)

\(2.4504e^{-5}\)

\(2.1089e^{-5}\)

\(3.2161e^{-5}\)

50

\(2.7134e^{-5}\)

\(2.3692e^{-5}\)

\(1.9880e^{-5}\)

\(1.7322e^{-5}\)

100

\(1.7091e^{-5}\)

\(1.6700e^{-5}\)

\(1.4650e^{-5}\)

\(1.3705e^{-5}\)

500

\(1.1898e^{-5}\)

\(1.1662e^{-5}\)

\(1.1497e^{-5}\)

\(1.1403e^{-5}\)

1,000

\(1.1697e^{-5}\)

\(1.3534e^{-5}\)

\(1.9545e^{-5}\)

\(1.6564e^{-5}\)

HOC

10

\(7.2104e^{-5}\)

\(1.1268e^{-5}\)

\(9.9271e^{-6}\)

\(9.3180e^{-7}\)

50

\(5.2183e^{-5}\)

\(1.6971e^{-5}\)

\(9.9128e^{-6}\)

\(9.3345e^{-7}\)

100

\(3.6107e^{-5}\)

\(1.6881e^{-5}\)

\(7.5263e^{-6}\)

\(9.2791e^{-7}\)

500

\(2.1945e^{-5}\)

\(1.5213e^{-5}\)

\(7.6298e^{-6}\)

\(8.4423e^{-7}\)

1,000

\(4.3177e^{-5}\)

\(2.2813e^{-5}\)

\(2.1970e^{-5}\)

\(9.9281e^{-7}\)