Design and Calculation for Splittered Axial Turbine Cascade

The reliability and improved thermodynamic performance of turbine–generator units have gained increasing importance recently. One way of achieving the optimization of HP performance in impulse steam turbine is to introduce multi–splitter cascade. This paper presents the design criteria about splittered axial turbine cascade as well as the blade airfoil generation, the placement and the number of splitter vanes are also discussed. In the second part of this paper, a new physical model is set up to determine outlet gas angle (or mass flow ratio). In addition, a procedure to calculate 2–D blade to blade flow field using variational FEM is presented in detail. Finally, experimental data are given to demonstrate the availiability of the presented calculation method.Copyright © 1993 by ASME