It is also shown, that this will decrease the emitted noise. Generation and propagation of turbulent spots on a water table are studied. A new photographic technique is developed to register structures within the spot. Streaks elongated in the streamwise direction are found to penetrate the spot, and it is observed that undulations on the streaks lead to chaotic motion. Comparisons with theory show that the theory accounts fairly well for the spreading angle, whereas the propagation speeds are larger than the observed values.
Frequency analysis shows, that the fundamental frequency and the variation are increased.
Hz are increased compared to those below 1000 Hz.