基于溶血估算的离心血泵设计

发布时间：2018-06-22 18:20

本文选题：人工心脏 + 溶血估算　；参考：《浙江大学》2011年硕士论文

【摘要】：心血管疾病是导致人类死亡的主要原因之一,全球人口的心脏病发病率高达1%,晚期心脏病导致的心力衰竭5年内死亡率高达75%,心脏移植是唯一的救治手段,然而供体的严重缺乏使得很多需要心脏移植的患者在等待供体中死去。所以,暂时性或永久性代替自然心脏功能的血泵就应运而生。人工心脏从最开始的搏动式血泵发展到最近的悬浮式旋转血泵,不断的解决心脏疾病中遇到的问题,更好的帮助患者脱离疾病。而且溶血和血栓一直以来是人工心脏临床应用中的重大难题。研究表明血泵内流动中的涡流区和滞止区对血泵溶血和血栓形成有很大的影响,并有学者给出了溶血估算的经验公式,该公式表明溶血的大小与红细胞在流动过程中所受的剪切应力和接触时间成幂函数关系。基于该溶血估算公式,本文针对血泵的溶血特性对离心式旋转血泵进行设计与优化,并进行了水力实验和溶血试验,主要开展以下三个方面的研究： 1)利用血泵设计的一元设计理论及速度系数法,并对血泵进行水力设计,同时本文提出一个平均剪应力模型,假定红细胞流经叶轮所受的平均切应力近似等效为红细胞流动过程中在单位体积单位路程下的动能增量。为了提高血泵溶血性能,本文通过减少红细胞流经叶轮的时间和降低它在此过程中所受平均应力的方法,基于平均剪应力模型对离心血泵进行参数化设计,进而改善溶血性能。 2)对模型血泵进行数值模拟及溶血估算分析,研究了叶轮和蜗壳在不同间隙下的水力特性及溶血性能,同时分析了叶片数对血泵的水力特性及溶血性能的影响,比较得到溶血性能较好的间隙大小和叶片数。 3)搭建水力实验平台和溶血试验台,对实体泵进行水力实验及溶血实验,进一步分析了血泵的水力特性及溶血特性。
[Abstract]:Cardiovascular disease is one of the main causes of human death. The incidence of heart disease in the world is as high as 1%, the death rate of heart failure caused by advanced heart disease is as high as 75% in 5 years. Heart transplantation is the only cure. However, the severe deficiency of the donor has made many patients who need the heart transplant to die in the donor. So, The temporary or permanent blood pump instead of the natural heart function came into being. The artificial heart developed from the beginning of the pulsating blood pump to the nearest suspending rotating blood pump to solve the problems encountered in the heart disease, and to help patients get out of the disease. And hemolysis and blood thrombus have always been in the clinical application of the artificial heart. A big problem.
The study shows that the eddy zone and the stagnation zone in the flow of blood pump have a great influence on the hemolysis and thrombosis of the blood pump, and some scholars have given the empirical formula for the estimation of hemolysis. The formula shows that the size of the hemolysis is a power function relationship with the shear stress and contact time of the red cell during the flow process. According to the hemolysis characteristics of the blood pump, the centrifugal rotating blood pump was designed and optimized, and the hydraulic experiment and the hemolysis test were carried out, and the following three aspects were mainly carried out.
1) based on the design theory of the blood pump and the velocity coefficient method, and the hydraulic design of the blood pump, an average shear stress model is proposed in this paper. It is assumed that the average shear stress of the red cell flow through the impeller is approximately equivalent to the kinetic energy increment at the unit volume single path in the process of red cell flow. By reducing the time of the flow of red blood cells through the impeller and reducing the average stress in the process, a parametric design of the centrifugal blood pump is designed based on the average shear stress model, and then the hemolysis performance is improved.
2) the numerical simulation of the model blood pump and the analysis of hemolysis were carried out. The hydraulic characteristics and hemolytic performance of the impeller and volute under different gaps were studied, and the effects of the number of blades on the hydraulic characteristics and hemolytic performance of the blood pump were analyzed, and the better gap and the number of leaves were compared.
3) build hydraulic experiment platform and hemolysis testbed, carry out hydraulic experiment and hemolysis test for solid pump, and further analyze the hydraulic characteristics and hemolytic characteristics of blood pump.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH311

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