Combining imaged based measurement techniques for V2527 engine flow characterization at an A320 in ground operation

Kurzfassung

Among the objectives of the DLR-project SAMURAI (Synergy of Advanced Measurement techniques for Unsteady and high Reynolds number Aerodynamic Investigations) the investigation of the flow and sound field upstream and downstream of a full scale aeroengine is aimed at providing important reference data required for reliable modeling and prediction. In this regard a wide variety of contactless and non-invasive laser optical and acoustic measurement techniques have matured in recent years to allow their application on full scale aircraft, both in stationary ground operation or even in-flight conditions. In September 2013 a week-long measurement campaign involved the DLR research aircraft A320-ATRA (Advanced technology research aircraft) inside a sound-attenuating hangar of Lufthansa Technik at Hamburg Airport. Within this campaign four image-based measurement techniques were applied in parallel to acquire data for the IAE V2527 engines operating at conditions varying between idle and take-off: • stereoscopic particle image velocimetry (PIV) of the engine intake and exhaust jet, • high frame rate background oriented schlieren (BOS) of the exhaust jet in combination with acoustic array measurements, • projected pattern correlation technique (PROPAC) for the measurement of fan blade deformation under load, • marker-based optical deformation measurements (MODE) to obtain reference positions of the aircraft during engine runs. The objective of the ground tests was to establish a combined measurement data base to locate the zones within the engine exhaust flow where large, turbulent fluctuations in velocity and density produce noise. Simultaneous application of PIV, BOS and acoustic array techniques were carried out in front and behind the aircraft jet engine for the characterization of inlet flow disturbance due to ground vortex formation, the turbulent free jet flow field as well as engine’s core and jet noise. The acquired data serves as a basis for validation of numerical simulations that aim at predicting engine performance and noise emission.