Investigation of the Effect of Roller Pump Geometry and Speed on Pulsation in Dialysis Tube

Standard hemodialysis (HD) units are employed for dialyzing uremic patients and utilize roller pumps to generate blood and dialysate flow. The Wearable Artificial Kidneys (WAK) are designed for continuous renal replacement therapy 24/7, requiring prolonged or continuous operation. Consequently, the fouling of the dialysis filter is a significant consideration for the WAK due to its restricted flow speed. The ultimate objective of this study is to develop a novel roller pump with the capability to prevent filter fouling in the dialyzer. In order to elucidate the optimal pump geometry conditions, we constructed a prototype roller pump and conducted experimental investigations on the variation coefficient of the outer pressure of the pump. The experimental results revealed that when using shells without bosses, pressure fluctuations remained minimal at practical flow velocities, making it challenging to achieve a pulsating function. Conversely, the addition of bosses to the surface demonstrated the potential to increase pressure fluctuation even under identical motor operating conditions.