Laser fringe anemometry for aero engine components

Advances in flow measurement techniques in turbomachinery continue to be paced by the need to obtain detailed data for use in validating numerical predictions of the flowfield and for use in the development of empirical models for those flow features which cannot be readily modelled numerically. The use of laser anemometry in turbomachinery research has grown over the last 14 years in response to these needs. Based on past applications and current developments, this paper reviews the key issues which are involved when considering the application of laser anemometry to the measurement of turbomachinery flowfields. Aspects of laser fringe anemometer optical design which are applicable to turbomachinery research are briefly reviewed. Application problems which are common to both laser fringe anemometry (LFA) and laser transit anemometry (LTA) such as seed particle injection, optical access to the flowfield, and measurement of rotor rotational position are covered. The efficiency of various data acquisition schemes is analyzed and issues related to data integrity and error estimation are addressed. Real-time data analysis techniques aimed at capturing flow physics in real time are discussed. Finally, data reduction and analysis techniques are discussed and illustrated using examples taken from several LFA turbomachinery applications.

[1]  R. G. Seasholtz.  Laser Doppler, velocimeter system for turbine stator cascade studies and analysis of statistical biasing errors , 1977 .

[2]  M. S. Reinath,et al.  A laser velocimeter system for large-scale aerodynamic testing , 1984 .

[3]  W. A. Bell,et al.  Aerodynamic measurements about a rotating propeller with a laser velocimeter , 1984 .

[4]  Richard G. Seasholtz,et al.  Combined fringe and Fabry-Perot laser anemometer for three component velocity measurements in turbine stator cascade facility , 1986 .

[5]  Dale Walker,et al.  Intrablade velocity measurements in a transonic fan utilizing a laser Doppler velocimeter , 1976 .

[6]  D. C. Wisler,et al.  Gas Velocity Measurements Within a Compressor Rotor Passage Using the Laser Doppler Velocimeter , 1973 .

[7]  R V Edwards,et al.  Implementation of a new type of time-of-flight laser anemometer. , 1986, Applied optics.

[8]  R. L. Evans,et al.  Turbulence and Unsteadiness Measurements Downstream of a Moving Blade Row , 1975 .

[9]  A. J. Strazisar,et al.  Laser Anemometer Measurements in a Transonic Axial Flow Compressor Rotor , 1981 .

[10]  L. J. Goldman,et al.  Three component velocity measurements using Fabry-Perot interferometer , 1984 .

[11]  S. K. Case,et al.  Window aberration correction in laser velocimetry using multifaceted holographic optical elements. , 1984, Applied optics.

[12]  A. J. Strazisar,et al.  Efficient laser anemometer for intra-rotor flow mapping in turbomachinery , 1980 .

[13]  R. Larguier.  Experimental Analysis Methods for Unsteady Flows in Turbomachines , 1981 .

[14]  R. P. Dring,et al.  Unsteady Three-Dimensional Turbine Aerodynamics , 1983 .

[15]  A. Melling,et al.  Seeding gas flows for laser anemometry , 1986 .

[16]  K. L. Orloff,et al.  Laser Doppler anemometer measurements using nonorthogonal velocity components: error estimates. , 1982, Applied optics.

[17]  H. Krain.  Experimental Observation of the Flow in Impellers and Diffusers , 1984 .

[18]  L. J. Goldman,et al.  Laser anemometer using a Fabry-Perot interferometer for measuring mean velocity and turbulence intensity along the optical axis in turbomachinery , 1982 .

[19]  A. J. Strazisar.  Application of laser anemometry to turbomachinery flow field measurements , 1985 .

[20]  H. Kruse,et al.  An Experimental Investigation Into the Effect of Wakes on the Unsteady Turbine Rotor Flow , 1985 .

[21]  A. J. Strazisar,et al.  Investigation of Flow Phenomena in a Transonic Fan Rotor Using Laser Anemometry , 1985 .

[22]  Alan H. Epstein,et al.  Rotor wake characteristics of a transonic axial flow fan , 1985 .

[23]  Albert K. Owen.  A parametric study of the beam refraction problems across laser anemometer windows , 1986 .