ADAPTIVE AND PARALLEL SIMULATIONS OF CARDIAC FLUID DYNAMICS AND ELECTROPHYSIOLO

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 该项目旨在对心脏的血液-肌肉-瓣膜力学和电生理学进行模拟，目的是进行心脏力学、流体动力学和电生理学的耦合模拟。虽然描述心脏力学和电生理学的方程不同，但我们使用一个共同的理论框架，即浸没边界(IB)方法来模拟心脏功能的两个方面。IB方法最初是作为流体-结构相互作用问题(如心脏流体力学)的一种方法引入的，但我们已将其扩展到描述心脏电生理学。我们开发了心脏力学和电生理学IB方法的统一软件实现。这个模拟框架提供了对分布式存储并行性和空间自适应的支持，从而使我们能够有效和高效地使用现代超级计算机。该项目的目标是使用该模拟框架(1)执行心脏电力学的多拍、全心模拟，(2)通过人体主动脉瓣模型执行极高分辨率的多拍血流模拟，以及(3)执行正常和病理生理的心室电生理学的高分辨率自适应双域模拟。在本项目中，我们还打算执行实质性的代码优化，并开始扩展该软件的工作，以使用混合并行编程模型，该模型使用OpenMP来实现节点内并行，使用MPI来实现节点间并行。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This project aims to perform simulations of the blood-muscle-valve mechanics and electrophysiology of the heart, with the goal of performing coupled simulations of cardiac mechanics, fluid dynamics, and electrophysiology. Although the equations that describe cardiac mechanics and electrophysiology are different, we employ a common theoretical framework, the immersed boundary (IB) method, to model both aspects of heart function. The IB method was introduced as an approach to problems of fluid-structure interaction (e.g., cardiac fluid mechanics), but we have extended it to describe cardiac electrophysiology. We have developed a unified software implementation of the IB approach to both cardiac mechanics and electrophysiology. This simulation framework provides support for distributed-memory parallelism and spatial adaptivity, thereby allowing us to use modern supercomputers effectively and efficiently. This project aims to use this simulation framework (1) to perform multi-beat, whole-heart simulations of cardiac electro-mechanics, (2) to perform extremely high resolution multi-beat simulations of blood flow through a model of the human aortic valve, and (3) to perform high resolution adaptive bidomain simulations of normal and pathophysiological ventricular electrophysiology. Within the present project, we also aim to perform substantial code optimization, and to begin work on extending this software to use a hybrid parallel programming model that employs OpenMP for intra-nodal parallelism and MPI for inter-nodal parallelism.