PIV Measurements of a Low-noise Top-mounted Propulsion Installation for a Supersonic Airliner

Bridges, James ; Wernet, Mark P

关键词: ACOUSTIC MEASUREMENT;    AERODYNAMIC NOISE;    EXHAUST SYSTEMS;    FAR FIELDS;    JET AIRCRAFT NOISE;    NOISE GENERATORS;    NOISE PREDICTION;    PARTICLE IMAGE VELOCIMETRY;    PLANFORMS;    PREDICTION ANALYSIS TECHNIQUES;    PROPULSION SYSTEM PERFORMANCE;    TURBULENT JETS;    VELOCITY DISTRIBUTION;   

RP-ID  :  GRC-E-DAA-TN63747

学科分类：声学和超声波

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

A model-scale exhaust system was tested to validate low-noise propulsion concepts and noise prediction methods. The tests involved far-field acoustics, phased array, and particle image velocimetry (PIV). This paper covers the particle image velocimetry portion. Data was acquired at NASA Glenn's Aero-Acoustic Propulsion Lab for a series of nozzles with different chevron designs, both uninstalled and installed on a representative aircraft planform. The impact of the various chevron treatments on the turbulent velocity field was documented, along with the impact of the pylon and planform. When correlated with far-field acoustic measurements and phased array measurements, reported in companion papers, the explanation of acoustic benefits from top-mounted propulsion is clear as is the path toward optimization of the concept.