Computational Aeroacoustic Analysis of Slat Trailing-Edge Flow

this paper will conform to the schematic of the experimental setup shown in Fig. 1. The view in Fig. 1 has been rotated from the physical orientation to one that is more intuitive. An enormous amount of data was collected and continues to be analyzed. Figure 2 illustrates one unexpected and until recently, perplexing feature of the experimental data. For the case in which the slat deflection, ffi s , is 30 degrees, a very large amplitude peak is observed in the acoustic spectrum in the vicinity of 50 kHz. This peak rises almost 20 dB above the signal observed for the case in which the slat is deflected 20 degrees. During the course of the experiment, efforts to eliminate the high-frequency peak by altering the overhang of the slat were largely unsuccessful. Only for cases in which the overhang became unrealistically large was a significant change in the high-frequency acoustic peak observed. Increasing the configuration 's angle-of-attack from 10 to 15 degrees, reduced the amplitude of the high-frequency peak by approximately 10 dB. For some time, no consistent explanation of the observed phenomena was available. The focus of this paper and a companion pape