for .

A series of computations was done for the single
and double layer cases. In the two examples presented
here, the initial data had the form

for , where

We calculate the solutions to time using an adaptive step
Runge-Kutta scheme of orders 7 and 8 [12], and by that time
the solution had achieved the form
and the wave speed (*c*) is estimated by evaluating
.

The results of the single layer simulation are shown in
the Figure 1. In this,
and the predicted wave speed is .
In Figure 2
we plot the numerical error, which is deviation of
our calculated solution from the theoretical solution
derived above

at . We see there that the error is

In the case of two layers, we take similar initial data for each of the two layers as described above, but we take . The results are shown in Figure 3 This simulation demonstrates that a striated structure can support different wave speeds.

2000-04-04