Collaborative Research: A New Three-Dimensional Parallel Immersed Boundary Method with Application to Hemodialysis

合作研究：一种新的三维平行浸入边界方法在血液透析中的应用

• 批准号: 1522554
• 负责人: Luoding Zhu
• 金额: $ 20.93万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1522554&HistoricalAwards=false
• 关键词: Collaborative; Research; New; Three; Dimensional

Fluid-structure interaction problems involving thin-walled structures are ubiquitous in biological and engineering applications. However, to date an efficient and effective technique, and a computational capability, for modeling and simulating the interactions between fluids and thin-walled structures are still sorely lacking. The investigators aim to design a new three-dimensional parallel immersed boundary method for computational simulation of fluid-thin-walled-structure interactions in a generic setting and apply it to blood flow past patient-specific distal anastomosis of arteriovenous grafts (AVG), which are essential to blood access of hemodialysis for numerous patients with end-stage renal disease. The new method, which will significantly broaden the applicability of immersed boundary methods, will be particularly valuable to the mathematical biology community for computational studies of vascular diseases such as vascular intimal hyperplasia, aneurysm, and atherosclerosis. Compared to existing models, the proposed computational model is more physiologically realistic: the simulation accommodates deformation of the vein/graft with the pulsatile blood flow, and it incorporates the small yet finite thickness of the vein/graft walls into the model. New computational results will clarify existing contradictory results in the literature regarding the force/flow characteristics near the distal AVG anastomosis and thus lead to a greater understanding of AVG-associated vascular intimal hyperplasia. The new method under development in this project will be generic and applicable to numerous significant problems in engineering, including parachute opening and novel design for street/highway signs. The studies will also enhance the understanding of vascular intimal hyperplasia due to dialysis, which may inspire the creation and development of novel vascular devices to prolong the patency rate of AVGs. This will not only improve quality of life for patients, but also offer savings in dialysis-related healthcare costs. The associated research and education activities will provide multidisciplinary training and research opportunities in mathematics, biology, scientific computing, fluid/solid mechanics, blood flows, and vascular disease for graduate students and undergraduates. The open source implementation of the new method will enable the fluid-structure-interaction community to dramatically increase their research productivity. The investigators will develop numerical methods to improve computational capability for fluid-thin-walled-structure interaction in three dimensions. They approach this type of problem by integrating several components: a structural component based on the high-order spectral/hp element technique, a fluid component based on the lattice Boltzmann method, and the coupling of the fluid and structure through the framework of the immersed boundary method. The goal of this project is three-fold: 1) Develop a three-dimensional IB-based method for fluid and thin-walled structure interactions in a general setting. The method will account for Newtonian and non-Newtonian fluids, material nonlinearity, and geometric nonlinearity. 2)Design, develop, and implement novel parallel algorithms for the new 3D method on hybrid CPU-GPU linux clusters. 3) Apply the new parallel method to model and simulate blood flow past the distal anastomosis of arteriovenous graft for hemodialysis using patient-specific data. The investigators' outreach activities will inspire high school students to consider careers in mathematical and computational sciences and raise public awareness for the dire consequences of end-stage renal disease, its associated healthcare costs, and the important roles mathematics and scientific computing play in studying disease and promoting health.

涉及薄壁结构的流固耦合问题在生物和工程应用中普遍存在。然而，迄今为止，仍然严重缺乏用于建模和模拟流体与薄壁结构之间相互作用的有效技术和计算能力。研究人员旨在设计一种新的三维平行浸入边界方法，用于计算模拟一般环境中的流体-薄壁-结构相互作用，并将其应用于经过患者特异性动静脉移植物远端吻合术（AVG）的血流，这对于许多终末期肾病患者的血液透析的血液通路至关重要。这种新方法将显着拓宽浸入边界方法的适用性，对于数学生物学界对血管疾病（如血管内膜增生、动脉瘤和动脉粥样硬化）的计算研究特别有价值。与现有模型相比，所提出的计算模型在生理上更加真实：模拟适应脉动血流引起的静脉/移植物的变形，并将静脉/移植物壁的小但有限的厚度纳入模型中。新的计算结果将澄清文献中关于远端 AVG 吻合附近​​的力/流特性的现有矛盾结果，从而更好地理解 AVG 相关的血管内膜增生。该项目正在开发的新方法将是通用的，适用于工程中的许多重大问题，包括降落伞打开和街道/高速公路标志的新颖设计。这些研究还将增强对透析引起的血管内膜增生的认识，这可能会激发新型血管装置的创建和开发，以延长 AVG 的通畅率。这不仅可以改善患者的生活质量，还可以节省透析相关的医疗费用。相关的研究和教育活动将为研究生和本科生提供数学、生物学、科学计算、流体/固体力学、血流和血管疾病方面的多学科培训和研究机会。新方法的开源实施将使流体-结构相互作用社区能够显着提高他们的研究生产力。研究人员将开发数值方法来提高三维流体-薄壁结构相互作用的计算能力。他们通过集成多个组件来解决此类问题：基于高阶谱/hp 元素技术的结构组件、基于格子玻尔兹曼方法的流体组件以及通过浸入边界法框架耦合流体和结构。该项目的目标有三个：1）开发一种基于三维 IB 的方法，用于一般环境中的流体和薄壁结构相互作用。该方法将考虑牛顿和非牛顿流体、材料非线性和几何非线性。 2)在混合CPU-GPU Linux集群上为新的3D方法设计、开发和实现新颖的并行算法。 3）应用新的并行方法，使用患者特定数据对经过血液透析动静脉移植物远端吻合口的血流进行建模和模拟。 研究人员的外展活动将激励高中生考虑从事数学和计算科学职业，并提高公众对终末期肾病的可怕后果、相关医疗费用以及数学和科学计算在研究疾病和促进健康方面发挥的重要作用的认识。

项目成果

Performance Analysis and Optimization of In-situ Integration of Simulation with Data Analysis: Zipping Applications Up

仿真与数据分析的现场集成的性能分析和优化：压缩应用程序

• 发表时间: 2018
• 期刊: HPDC 2018
• 作者: Fu, Y.;Li, F.;Song, F.;Chen, Z.
• 通讯作者: Chen, Z.

Building a scientific workflow framework to enable real‐time machine learning and visualization

构建科学的工作流程框架以实现实时机器学习和可视化

• 发表时间: 2018
• 期刊: Concurrency and computation
• 作者: Li, F.;Song, F.
• 通讯作者: Song, F.

Scaling Up Parallel Computation of Tiled QR Factorizations by a Distributed Scheduling Runtime System and Analytical Modeling

通过分布式调度运行时系统和分析建模扩展平铺 QR 分解的并行计算

• 发表时间: 2018
• 期刊: Parallel processing letters
• 影响因子: 0.4
• 作者: Zheng, W.;Song, F.;Lin, L.;Chen, Z.
• 通讯作者: Chen, Z.