Abstract:

Airfoil trailing edge scattering noise is a significant component of airfoil self-noise， commonly found in the noise of fast-moving bodies rotating machinery. A rapid prediction method for airfoil trailing edge scattering noise based on the wavenumber-frequency spectrum of turbulent boundary layer pulsating pressure （referred to as “TBL（Turbulent boundary layer） pulsating pressure”） can achieve fast noise prediction. However， existing methods lack sufficient consideration of compressibility when modeling the TBL pulsating pressure wavenumber-frequency spectrum， leading to weak universality in media with significant differences in compressibility， such as water and air. This paper establishes a new prediction method for airfoil trailing edge scattering noise based on a compressible theorybased TBL pulsating pressure wavenumber-frequency spectrum model， combined with Amiet’s airfoil far-field noise propagation integral model. Acoustic wind tunnel and water tunnel experiments were conducted to obtain experimental data on TBL pulsating pressure and far-field noise on airfoil surfaces in both air and water media， to verify the model， and to compare it with the classic Chase Ⅱ model， which also considers compressibility. The results indicate that the new method demonstrates general applicability and high accuracy in both air and water， and its prediction performance for TBL pressure fluctuations and noise in air and water surpasses that of the Chase Ⅱ model.

Key words: trailing edge scattering noise, rapid prediction method, pulse wave number-frequency spectrum, compressibility-based prediction model, aeroacoustic wind tunnel, water tunnel