Efficient elliptic solver for the mild slope equation using BI-CGSTAB method

The elliptic mild slope equation is used to simulate linear wave propagatio n over variable sea bed topography with mild slopes. The governing equation is discretized by the finite difference method. Based on the BI-CGSTAB tec hnique, an attractive variant bf BI-Conjugate Gradients (BI-CG) method, the obtained linear algebraic system of equations is solved. Numerical experim ents show that the BI-CGSTAB method is efficient for solving the elliptic m ild slope equation. The results obtained by the BI-CGSTAB-Based method are much the same as those obtained by other authors with different solution me thods, but the convergence rate is much faster than that of other methods.