Hello,
Post-processors may give slightly different values of discharges for different reasons, I give two here:
1) in Telemac the output discharge is deduced from the continuity equation in the last row of elements, independently of the velocities. As generally the output has prescribed depths which are treated as Dirichlet values, the continuity equation is not solved in these points, hence the velocities given at the exit may not fully obey the continuity. The post-processors have only the velocities at the exit to evaluate the discharge.
2) in Telemac-2D the discharge is an integral of the depth multiplied by the velocity, which is thus a quadratic function. Post-processors will multiply the depth by the velocity and consider that it gives a linear function, hence a small discrepancy.
With best regards,
Jean-Michel Hervouet
