Characteristics and suppression of flow pulsation from peristaltic pump.

Characteristics of the ripple in the liquid flow through a peristaltic pump was detected quantitatively as pressure fluctuation by using a silicon-pressure sensor. The ripple was associated with the rotation of the squeezing rollers and it could be caused by the periodic release of tension on a flexible tube. At the slow rotation of rollers, i.e., slow pumping speed, the negative pulse on smooth flow was observed, but the ripple on flow was rather complex at the faster rotation, and finally it became periodic. Moreover, ripple was larger for tubes of smaller internal diameters. An air damper consisting of simple glass cylinder was available to reduce these ripples.