Design and experimental verification of dialyzer end cap based on helical flow

TENG Weihang; LI Qingnian; ZHA Lei; BAO Wenliang; XIONG Yan; FU Ping

doi:10.19529/j.cnki.1672-6278.2026.02.10

Abstract：To address the critical issue of internal coagulation within the dialyzer that affects the safety and efficiency of hemodialysis,we designed a helical flow guide vane integrated into the arterial end of the dialyzer.Firstly,based on the computational fluid dynamics(CFD)method,the coefficient of variation(CV)of blood flow at the end face of the fiber bundle and the wall shear stress(WSS)were used as the key hemodynamic indicators for predicting the risk of coagulation to conduct fluid dynamics simulation on the helical flow guide vanes.Sec-ondly,the optimal configuration of the helical flow guide vanes was determined through multi-objective optimization design,and 3D printing processing was carried out.Finally,in vitro bovine blood circulation experiment was conducted.The rate of increase in transmembrane pres-sure(TMP)was used as a macroscopic indicator to characterize the overall coagulation process.The anticoagulation performance of the exper-imental group and the control group was tested.The simulation results showed that the optimized helical flow guide vanes could induce helical flow in the fiber bundle area.The CV of the optimized model was reduced by 59.00%,and the proportion of the low WSS area at the end face of the fiber bundle was reduced by 69.24%,indicating the elimination of the low-speed stagnation zone in the end cap and the reduction of the initial risk of coagulation.In vitro anticoagulation experiments also indicated that the rate of TMP increase in the experimental group was 9.37%,slower than that in the control group,proving that the coagulation problem was improved.The structure of the helical flow guide vanes can delay the coagulation process within the dialyzer by improving the uniformity of blood flow and WSS of the dialyzer.The research can pro-vide new ideas and theoretical basis for the development of high-performance hemodialyzers with low anticoagulant dependence.