Blood damage and turbulence: in vitro study of the turbulence-induced hemolysis in a Taylor-Couette-System

血液损伤和湍流：Taylor-Couette 系统中湍流引起的溶血的体外研究

• 批准号: 507267166
• 负责人: Professor Dr.-Ing. Leonid Goubergrits
• 金额: --
• 依托单位: Institut für Kardiovaskuläre Computer-assistierte Medizin (CVK)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/507267166?language=en
• 关键词: Blood; damage; turbulence; vitro; study

Blood damage caused by turbulence is a huge problem in the clinical use of cardiovascular implants such as ventricular assist devices. Objective: The objective of the project is to investigate the blood damage caused by turbulence in-vitro. This has not yet been achieved, as turbulence chambers commonly used in fluid mechanics are not suited for investigation of blood flows. Using an experimental turbulence chamber, a Taylor-Couette system (TCS) with counter-rotating cylinders, turbulence can be generated, and blood damage caused by turbulent flow features can be investigated experimentally. State of the art: The importance of blood damage for ventricular assist devices is judged as an important issue in the international literature. A variety of damage models is presented, but there is a lack of consensus between the respective models as well as between models and underlying experiments. Currently, there is no in-vitro model known, which permits to subject a limited blood volume to a defined turbulence. Hypothesis: The hypothesis is, that blood damage caused by turbulence can be experimentally investigated in a special TCS. In this flow chamber the inner and the outer cylinder can be rotated independently from each other. When counter rotating with distinct rotational speeds, featureless turbulence is generated in the gap between both cylinders. So far, this effect was not yet used for the investigation of blood damage due to turbulence flows. Furthermore, a nearly homogenous laminar shear flow with similar average shear rates can be generated in the same Couette flow chamber. Using this feature, a direct comparison between laminar and turbulent flow conditions can be performed. Methods: Using the TCS with counter rotating cylinders, a turbulent flow is generated in the gap. Using the same flow chamber, the fluid in the gap can be subjected to laminar and turbulent shear flow with the same average shear rate. The flow characters are investigated using a test fluid modelling the multiphasic behavior of blood and a two velocity-component LDA probe. Characteristic turbulence parameters are assessed as a function of rotational speed and effects of flow conditions, turbulence intensity, time will be investigated as well as the variance of those turbulent parameters. For the assessment of blood damage, blood samples of animals and healthy volunteers are investigated with current clinical standard methods. Finally, a model for prediction of blood damage based on turbulence parameters will be developed.

湍流引起的血液损伤是临床使用心血管植入物（如心室辅助装置）的一个巨大问题。目的：研究体外湍流对血液的损伤。这还没有实现，因为流体力学中常用的湍流室不适合研究血流。在实验紊流室中，采用具有反向旋转柱体的Taylor-Couette系统（TCS），可以产生紊流，并对紊流特性对血液的损伤进行实验研究。现状：在国际文献中，血液损伤对心室辅助装置的重要性被认为是一个重要的问题。虽然提出了多种损伤模型，但各个模型之间以及模型与基础实验之间缺乏一致性。目前，还没有已知的体外模型，它允许将有限的血容量置于确定的湍流中。假设：假设是，湍流引起的血液损伤可以在一个特殊的TCS中进行实验研究。在这个流室中，内筒和外筒可以彼此独立地旋转。当以不同转速反向旋转时，两个气缸之间的间隙会产生无特征的湍流。到目前为止，这一效应还没有被用于研究湍流引起的血液损伤。此外，在相同的Couette流室中，可以产生具有相似平均剪切速率的几乎均匀的层流剪切流。利用这一特性，可以直接比较层流和湍流的流动条件。方法：采用对向旋转圆柱体的TCS，在间隙内产生湍流。在相同的流室中，间隙内的流体可以以相同的平均剪切速率进行层流和湍流剪切流动。使用模拟血液多相行为的测试流体和双速度分量LDA探针研究了流动特性。特征湍流参数被评估为转速的函数，流动条件、湍流强度、时间的影响以及这些湍流参数的方差将被研究。为了评估血液损伤，采用现行的临床标准方法对动物和健康志愿者的血液样本进行了调查。最后，建立了基于湍流参数的血流损伤预测模型。