ANCHORED EDGE PITCHING RESPONSE OF A SPINNING FRICTIONLESS LIQUID COLUMN DUE TO BOTTOM AND/OR TOP EXCITATION

The response of an anchored spinning frictionless liquid bridge to different pitching top and/or bottom excitation has been determined. The free surface displacement is obtained for synchronous, counter-excited and one-sided pitching excitation as a function of the dimensionless forcing frequency {Mathematical expression}. The contactlines at the rim of the upper and lower discs are considered to be anchored. In synchronous pitching excitation only the even resonances show response peaks, while in a counter-excited system only odd resonances appear, which is in contrast to axial excitation modes. For one-sided excitation, all reasonances appear. Because of the different natural frequencies in direction of spin and opposite to it double peaks are present in the responses. © 1995 VDI-Verlag GMBH.