A three-dimensional potential flow solution for a turbine stator has been obtained by solving the Laplace equation in an interior domain with open surface. The Fredholm integral equation of the second kind formulated for an interior Neumann problem has been applied to solve the turbine-stator flow. The open surface in this approach is replaced by the corresponding solid angle. Vortex filaments are used to simulate lifting surfaces. Global iterations for surface-panel source densities and vortex strengths are used in conjunction with Neumann iterations for solving the integral equation. A special treatment on the kernel is adopted in the solution scheme of the integral equation. It is found that numerical solutions converge within 20 iterations and they are satisfactory in comparison with the existing experimental data.