Investigation of Unsteady Aerodynamic Blade Excitation Mechanisms in a Transonic Turbine Stage—Part I: Phenomenological Identification and Classification

Based on the results of time-dependent 3-D viscous computations the aerodynamic mechanisms that cause the unsteady pressure fluctuations on the vane and rotor blade surface of a high-pressure transonic turbine are identified and separately classified in a phenomenological manner. In order to be able to describe separately the influence of wake, potential and shock distortions on the blade surface pressure tit design operation conditions, the stator exit Mach number is increased as to enhance the shock distortions and lowered as to enhance potential anti wake distortions, In a comprehensive approach the observations from the off-design conditions are utilized to classify every major perturbation observed in the perturbation space-time maps tit design operation conditions. The spanwise variations caused by the inherent 3-D nature of the flow field and promoted by the 3-D shape of the rotor blade are addressed.

[1]  Budugur Lakshminarayana,et al.  Unsteady Viscous Flow Causing Rotor-Stator Interaction in Turbines, Part 1: Data, Code Pressure , 2000 .

[2]  Aspi Rustom Wadia,et al.  Inlet Distortion Generated Forced Response of a Low Aspect Ratio Transonic Fan , 1996 .

[3]  Reza S. Abhari,et al.  Influence of Vane-Blade Spacing on Transonic Turbine Stage Aerodynamics: Part II—Time-Resolved Data and Analysis , 1999 .

[4]  D. C. Wisler,et al.  Unsteady Aerodynamics and Gust Response in Compressors and Turbines , 1992 .

[5]  M. D. Lefcort.  An Investigation Into Unsteady Blade Forces in Turbomachines , 1965 .

[6]  H. Hodson.  Measurements of wake-generated unsteadiness in the rotor passages of axial flow turbines , 1985 .

[7]  Michael B. Giles,et al.  Calculation of Unsteady Wake/Rotor Interaction , 1987 .

[8]  Torsten Fransson,et al.  Investigation of the Flowfield in the Transonic VKI BRITE EURAM Turbine Stage With 3D Steady and Unsteady N-S Computations , 2000 .

[9]  D. L. Schultz,et al.  Unsteady Aerodynamic and Heat Transfer Processes in a Transonic Turbine Stage , 1985 .

[10]  Michael G. Dunn,et al.  Investigation of unsteady flow through a transonic turbine stage : data/prediction comparison for time-averaged and phase-resolved pressure data , 1992 .

[11]  Howard P. Hodson,et al.  An Inviscid Blade-to-Blade Prediction of a Wake-Generated Unsteady Flow , 1985 .

[12]  Roger W. Ainsworth,et al.  The unsteady pressure field over a turbine blade surface: visualisation and interpretation of experimental data , 1997 .

[13]  R. A. Delaney,et al.  Vane-blade interaction in a transonic turbine. I - Aerodynamics , 1994 .

[14]  M. Giles,et al.  Predictions of Three-Dimensional Steady and Unsteady Inviscid Transonic Stator/Rotor Interaction With Inlet Radial Temperature Nonuniformity , 1994 .

[15]  U. K. Singh,et al.  UNSTEADY FLOW IN A SINGLE STAGE TURBINE , 1998 .

[16]  Denis J. Doorly,et al.  Simulation of the Effects of Shock Wave Passing on a Turbine Rotor Blade , 1985 .

[17]  Budugur Lakshminarayana,et al.  Unsteady Viscous Flow Causing Rotor-Stator Interaction in Turbines, Part 2: Simulation, Integrated Flowfield, and Interpretation , 2000 .

[18]  Guillermo Paniagua,et al.  Investigation of the Unsteady Rotor Aerodynamics in a Transonic Turbine Stage , 2000 .

[19]  Hans Mårtensson,et al.  Numerical Simulation of a Film Cooled Nozzle Guide Vane Using an Injection Model , 1998 .

[20]  Guillermo Paniagua,et al.  Experimental investigation of the unsteady rotor aerodynamics of a transonic turbine stage , 1999 .