Mechanical and Aerospace Engineering Department, University of California, Los Angeles, CA, USA.
Department of Surgery, University of California, Los Angeles, CA, USA.
Med Biol Eng Comput. 2021 Jan;59(1):227-242. doi: 10.1007/s11517-020-02283-w. Epub 2021 Jan 8.
Modeling the coupled fluid and elastic mechanics of blood perfused soft tissues is important for medical applications. In particular, the current study aims to capture the effect of tissue swelling and the transport of blood through damaged tissue under bleeding or hemorrhaging conditions. The soft tissue is considered a dynamic poro-hyperelastic material with blood-filled voids. A biphasic formulation-effectively, a generalization of Darcy's law-is utilized, treating the phases as occupying fractions of the same volume. A Stokes-like friction force and a pressure that penalizes deviations from volume fractions summing to unity serve as the interaction force between solid and liquid phases. The resulting equations for both phases are discretized with the method of smoothed particle hydrodynamics (SPH). The solver is validated separately on each phase and demonstrates good agreement with exact solutions in test problems. Simulations of oozing, hysteresis, swelling, drying and shrinkage, and tissue fracturing and hemorrhage are shown in the paper. Graphical Abstract In the paper, a new methodology for the numerical simulation of the full dynamic response of blood-perfused soft tissues was developed.
对灌注血液的软组织的流固耦合力学建模对医学应用非常重要。特别是，本研究旨在捕捉在出血或出血情况下组织肿胀和血液通过受损组织运输的影响。软组织被认为是一种具有充满血液的空隙的动态多孔超弹性材料。两相公式——实际上是达西定律的推广——被用来处理占据相同体积分数的相。作为固液相间相互作用的力，有一个类似于斯托克斯的摩擦力和一个惩罚体积分数之和不为 1 的压力。两相的方程都用光滑粒子流体动力学（SPH）方法离散化。求解器在每个相上分别进行验证，并在测试问题中与精确解表现出很好的一致性。本文展示了渗出、滞后、肿胀、干燥和收缩以及组织破裂和出血的模拟。
