A low-dimensional model for the red blood cell

Abstract

The red blood cell (RBC) is an important determinant of the rheological properties of blood because of its predominant number density, special mechanical properties and dynamics. Here, we develop a new low-dimensional RBC model based on dissipative particle dynamics (DPD). The model is constructed as a closed-torus-like ring of 10 colloidal particles connected by wormlike chain springs combined with bending resistance. Each colloidal particle is represented by a single DPD particle with a repulsive core. The model is able to capture the essential mechanical properties of RBCs, and allows for economical exploration of the rheology of RBC suspensions. Specifically, we find that the linear and non-linear elastic deformations of healthy and malaria-infected cells match those obtained in optical tweezers experiments. Through simulations of some key features of blood flow in vessels, i.e., the cell-free layer (CFL), the Fahraeus effect and the Fahraeus-Lindqvist effect, we verify that the new model captures the essential shear flow properties of real blood, except for capillaries of sizes comparable to the cell diameter. Finally, we investigate the influence of a geometrical constriction in the flow on the enhancement of the downstream CFL. Our results are in agreement with recent experiments.

Probing red blood cell mechanics, rheology and dynamics with a two-component multi-scale model

“…The real size of a DPD particle may vary from one to several dozens of atoms, depending on the interaction potential and the time scale. Several recent papers have dealt with this issue and have attempted to map the computed results into dimensional units [20,[25][26][27][28]. A mapping strategy developed by Fedosov et al [20] is adopted to provide an estimate of the physical length and time scales in the DPD simulations of RBC flow.…”

A two-phase model of blood flow in large and small blood vessels

“…dumbbells) из эритроцитов. В работе [6] каждый эритроцит моделируется закрытым тором, состоящим из 10 коллоидных частиц, связанных "цепью" между собой. Дальше численно моделируется движение таких эритроцитов в плазме и проводится сравнение с экспериментом (эффектами Фареуса и Фареуса-Линдквиста).…”

Understanding the mechanisms of sickle cell disease by simulations with a discrete particle model

“…For the spring force, a worm-like chain (WLC) force [8] was used. The WLC force, often used to simulate biological systems such as DNA, was believed to have properties that would more realistically simulate RBC behavior and has been successfully in simulating RBC previously [9].…”