Experimental study of hydrodynamic propulsion of a medical device with a spiral ribbed impeller

In order to minimize injury during a medical treatment using a low invasive sliding device, loss of cells and tissues due to wear against the device m ust be prevented by maintaining good lubrication condition. For this purpos e, a new medical device with a spiral ribbed impeller has been presented. T his paper shows the potentials and problems of the proposed mechanism throu gh experiments. The experimental result confirms that a device can be drive n by thrust force keeping noncontacting condition. In some cases, however, the measured thrust force was lower than the theoretical prediction. Cavita tion was observed through the transparent impeller in a visualized experime nt. It is suggested that a rupture of fluid film associated with cavitation may limits the thrust force and injure tissues. Viscous liquid should be s upplied to suppress cavitation if the quantity of the existing mucus is not sufficient. (C) 1998 Elsevier Science S.A. AU. rights reserved.