基于离散元法的血细胞颗粒破碎机理及血泵溶血指数模型研究

血泵作为挽救心血管疾病和心脏病患者生命的重要辅助装置，它既要满足人体血液循环流体力学性能，更要满足血液生理指标，然而常规的血泵设计大都从宏观血液循环指标入手，而对血液生理指标基本上从实验中来，不能在血泵设计阶段准确的揭示血细胞颗粒破碎的真实成因,极大地影响了血泵的进一步发展和临床应用。本项目基于颗粒离散元法提出一种接近真实几何、力学特性的双凹软椭球红细胞接触模型，通过研究分子尺度的血细胞流动、流变特性、血细胞三维DEM颗粒破碎动力学行为以及复杂液固气多相流运动分布规律等科学问题，揭示血细胞颗粒碰撞、空蚀破碎机理，建立基于CFD-DEM技术的血细胞力学特性与血液流变耦合溶血指数模型，提出一种同时满足血细胞微观生理性能和血液宏观流体力学性能的血泵设计方法。

Blood pump is an important auxiliary device to save lives for patients with cardiovascular disease or heart disease. It is not only to meet the body's blood circulation hydrodynamic performance, but also to meet the physical properties of blood. However, most of the conventional blood pump designed from the start of macro indicators of blood circulation, and most of the physiological indicators of blood coming from the experiment, cannot accurately reveal the true causes of blood cells particle crushing in the design stage of the blood pump, which had greatly influenced the further development and clinical application of blood pump. Based on the particle discrete element method (DEM) and CFD-DEM coupling techniques, a biconcave ellipsoid red blood cell (RBC) contact model with real geometry, mechanical properties of erythrocyte is put forward. Through studying on some scientific issues, such as the RBC rheological dynamics characteristics, the DEM 3-D particle broken dynamical behavior, the complex liquid-solid-gas multiphase flow distribution law, blood cell particle collision, cavitation breakage mechanism is revealed. The prediction model is established with blood cell mechanical properties and blood rheological coupled hemolytic based on CFD-DEM Technology. Then, a design method for blood pump is proposed to meet the RBC microscopic physiological performance and the blood macroscopic hydrodynamic performance.