p - p t K (16) 



where p Is the density of the fluid. 



CONTROL PLANS 



The velocity potential for the control plane, whose coordinate system la 

 shown in Figure 2, la expressed in the two-dimensional domain as 



«V(x,z) - -Dx + <Kx,z) (17) 



where 4> Is tho disturbance velocity potential due to a section of the control 

 plane. This disturbance potential satisfies the following conditions. 



1. Laplace equation in the fluid dota3in 



^f + ^f-0 (18) 



dx OS 



2. The linearized free-surface condition 



^!| +ko M- (19) 



ax 02 



3. The body boundary condition 



M - Un. \ (20) 



5n 



k. Kutta condition: the velocities at the trailing edge elements, one at 

 the top of the surface ana one at the bottom, are equal. 



In addition, the disturbance potential should satisfy radiation and bottom 

 conditions siailar to Equations (5) and (6). 



