3. Solution to radiated and diffracted potentials
To obtain the radiated and diffracted potentials, we divide the fluid domain into three
subdomains I, II and III as shown in Fig. 1. Here the radiated potentials in the three
subdomains are denoted by 4ðLÞ
R1 , 4ðLÞ
R2 and 4ðLÞ
R3 , and the diffracted potentials are expressed
by FD1, FD2 and FD3, respectively. The method of separation of variables is applied in
each subdomain to obtain the expressions for the radiated and diffracted potentials with
unknown coefficients. The coefficients are then solved by use of the eigenfunction
expansion matching method, which has been used by many investigators.