Kidney diseases, consisting in a total or partial loss of renal function for the patients, are rapidly increasing over the years. Nowadays, the most common treatment to replace kidney’s functionality is hemodialysis, which filter waste, salts and fluid from patient’s blood by an extracorporeal machine. The core element of the hemodialysis machine is the dialyzer: a filter in which a porous film (i.e., a bundle of fibers) separates blood from the dialysate fluid (with which blood exchanges solutes and toxins). The dialysate flows outside the bundle of fibers while the blood flows inside the fibers. Because the efficacy of hemodialysistherapy depends on the fluid dynamic inside the dialyzer, several computational models were proposed to study the hollow fiber membrane-based hemodialysis process, but only a few used a 3D approach, and none of them reproduced high-fidelity geometry of the filter.