Momentum transfer in jet excitation of flute-like instruments
John W. Coltman · The Journal of the Acoustical Society of America · 1981
The excitation of flutes and organ pipes takes place partly by transfer of jet momentum, and partly by insertion of a pulsating volume of air into the pipe. An experimental determination of the relative importance of these two mechanisms was made by exciting a symmetrical resonant pipe with a pulsed jet source whose direction could be varied. The change in response with direction of the jet served to distinguish momentum transfer excitation from volume insertion excitation. The momentum effects were roughly of the magnitude expected, but the phase of the excitation, and the variation with steady airflow did not follow the simple theory. Momentum transfer was also demonstrated in a blown pipe.