Three dimensional numerical tools are now commonly used in the design or analysis process of the internai flow of hydraulic machinery. As an illustration of the use of such tools to study the internai flow of a Francis turbine, the computational results obtained in all components of this turbine with an Euler equations solver and two Reynolds Averaged Navier Stokes equations solvers are discussed. The analysis process is illustrated and comparisons with experimental results obtained in the spiral casing and at the outlet of the guide vaoes, runner and draft tube are presented.