This test is based on Ebrahimi et al.50 experimental set up reported on

the transmission of the tidal oscillations in a lagoon. In this test a

trapezoidal barrier build of non cohesve sand seperates a closed lagoon from

the sea(fig. 14). Porosity and intrinsic permebelity of the barrier are 0.3 and

, respectively. The water level in the open sea was

fluctuated with an amplitude of 60 mm and a period of

to apply the boundary

conditions. Figure 14 illustrates the dimensions of experimental setup and the

boundary conditions of the problem. Points A, B and C illustrated in this

figure are the places where the solutions are going to be presented and

compared with the experimental obsorvations. Point A and point B displays water

level fluctuations in the lagoon and in the open sea, respectively. On the

other hand, point C is used to illustrate the velocity fluctuations in the open

sea. More detailed descriptions of the measurements and data my be found in

Ebrahimi et. al. 50 and in Yuan et al. 26. Konga et al. 25 and Li et al.23 have been

studied this experiment using finite volume/finite difference and control

volume methods, respectively. Here this experiment is solved with the use of the

new procedure of free surface tracking presented in this paper. To do so, the grid

size is taken as

in tiangular shape. The

surface water level fluctuations evaluated in this paper

are compared with the experimental obsorvation in Figures 15 and 16 for point B and A, respectively, where an excellent

aggrement exists between two results. Moreover, the flow velocity predicted by

the present model for point C is compared with the experimental obsorvation in

Fig.17, where again an excellent matches achieved. It is worth mentioning that Reynolds number in this problem is less than 10, and Darcy assumption is acceptable to a

large extent12