An Experimental Study of the Aerodynamic Forcing Function in a 1.5 Steam Turbine Stage

TitleAn Experimental Study of the Aerodynamic Forcing Function in a 1.5 Steam Turbine Stage
Publication TypeConference Paper
Year of Publication2016
AuthorsGatti G, Gaetani P, Paradiso B, Dossena V, Arcangeli L, Maceli N, Bellucci J
Conference NameASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition
Volume8: Microturbines, Turbochargers and Small Turbomachines; Steam Turbines
PaginationV008T26A020; 9 pages
Conference LocationSeoul, South Korea, June 13–17, 2016
ISBN Number978-0-7918-4986-6
KeywordsAlgorithms, Blades, Computation, Engineering simulation, Flow (Dynamics), Pressure, Probes, Rotors, Steam turbines, Torque

    The usual ways to measure the aerodynamic forcing function are complex and expensive. The aim of this work is to evaluate the forces acting on the blades using a relatively simpler experimental methodology based on a time-resolved pressure measurement at the rotor discharge. Upstream of the rotor, a steady three holes probe has been used. The post processing procedures are described in detail, including the application of a phase-locked average and of an extension algorithm with phase-lag. The algorithm for the computation of the force components is presented, along with the underlying assumptions. In order to interpret the results, a preliminary description of the flow field, both upstream and downstream of the rotor, is provided. This gives an insight of the most relevant features that affect the computation of the forces. Finally, the analysis of the results is presented. These are first described and then compared with overall section-average results (torque-sensor), and with the results from 3D unsteady simulations (integral of pressure over the blade surface) in order to assess the accuracy of the method. Both the experimental and the numerical results are also compared for two different operating conditions with increasing stage load. 



Refereed DesignationRefereed