Fluid dynamics optimization of a Steam Turbine last three low pressure stages

Giorgio Turozzi

Franco Tosi Meccanica


The work is part of the design of an axial steam turbine (rated power of 160 MW), produced by Franco Tosi Meccanica Spa. This is an optimization activity, performed in collaboration with Enginsoft, aimed at the design review of the last three low pressure stages statoric rows, in order to maximize the total to total isentropic efficiency.

The optimization software ModeFRONTIERâ„¢ is used to control the work flow that automatically manages both the exploration of different design points, both the management of the fluid dynamics simulations (geometry generation, model pre-processing, solution and post-processing by means of the tools provided by the package Ansys Workbench).

Thanks to a valid choice of input parameters, output values, targets and project constraints, using efficient optimization algorithms, a wide exploration of the parametric space is performed. With the modifications adopted, the maximum expected increase in performance was calculated to be approximately 0.7%.