DISCRIMINATING METHOD FOR OSCILLATION MODE IN CIRCUMFERENTIAL DIRECTION OF CYLINDRICAL VESSEL HAVING FREE LIQUID SURFACE

摘要

PURPOSE:To obtain a method by which oscillation modes in the circumferential direction of a cylindrical vessel can be discriminated instantaneously by observing the state of the ripples produced on the free liq. surface of the liq. stored in said vessel optically. CONSTITUTION:A camera 22 and a lamp 23 which radiates a free liq. surface are installed above the opening part of a cylindrical vessel 20 in which liq. 21 forming the free liq. surface is stored. The lamp 23 is installed at such an angle at which only the reflected light from the waveform regions A formed in the positions corresponding to the films of the oval oscillations generated in the circumferential direction of the vessel 20 enters the camera 22 owing to said oscillations. The modes and order of the oval oscillations generated in the vessel 20 are discriminated by observing the number and sizes of the waveregions A that appear glittering white in the photographed pictures.