Suppression of flow pulsations and energy consumption of a drug delivery roller pump based on a novel tube design

Abstract

A drug infusion peristaltic pump is experimentally studied, examining its performance for three flexible tubes, two cylindrical, and an innovative one of lenticular cross-section with an inflated part. Using water as flowing medium, the pump outlet flow rates were measured at nine phases of the semi-period, based on phase-locked 2D-PIV data. The roller disengagement phase showed to cause a reduction of the outlet flow rate, and in a lesser degree, the engagement phase. Flow acceleration at the pump outlet occurred when only one roller was squeezing the tube. The gauge pressure waveforms at the pump inlet and outlet although noisy had a phase lead with respect to the flow rate. According to the pump motor current waveform, the work of the forces necessary for the tube deformation was about 10 times higher than that of the fluid viscous and inertial forces. Among the three examined flexible tubes, the pump performance was the best when the lenticular tube was used, presenting the highest volumetric efficiency and the smallest outlet flow rate pulsations, pressure amplitudes, and energy consumption. The high pump performance is attributed to the innovative inflated part of the lenticular tube, its cross-sectional shape and its higher compliance compared to the other tubes.