Design and analysis of a hemodializer with increased filtration performance

It is known that hemodialysis is of vital importance for kidney patients and the length of the dialysis session negatively affects the life of the patients. Therefore, improving the performance of the hemodialyzer, which is a part of the hemodialysis unit, is of critical importance for kidney patients. This study aims to increase hemodialyzer filtration performance. For this reason, changes in the urea clearance value, which is a measure of the amount of urea cleared in the blood, were investigated for a hemodialyzer using a membrane with a porous structure. It has been tried to increase the filtration performance by managing the lumen and dialysate flows formed along the fiber membranes with micron diameter with the pressure-driven flow and increasing the membrane surface roughness. For surface roughness, micro-pillars with Gaussian function shape were applied to the single and both surfaces of the membrane. Two different models were used for the fluid on the lumen and dialysate sides: Newtonian type and non-Newtonian type suitable for the viscosity model of blood. According to the simulation results, it was observed that the membrane surface roughness increased the filtration performance of the hemodialyzer. It has been revealed that this increase occurs when the fluctuation in the flow around the membrane surface increases the material transport.