Tech Briefs


Fluid-structure Interaction Analysis of Red Blood Cell

ADINA is widely used in biomechanical applications. In this News we present an application of ADINA FSI to the mechanical study of a red blood cell (RBC). The model consists of an incompressible hyperelastic membrane including viscoelastic effects (representing the cell membrane), filled with an incompressible Newtonian fluid, representing the cytoplasm (Figure 1). The aim is to investigate the mechanical properties of the RBC using numerical simulation and to compare the result with experimental data (see Ref.).



Figure 1 Schematic of the model


The model is subjected to axial tension along one of its diameters and a transient dynamic analysis is performed. Two-way coupling of the membrane and cytoplasm is considered. Figure 2 and the animation above depict the deformed shape of the RBC for different tensile forces. Due to symmetry only one-eighth of the cell is modeled.



Figure 2 Snapshots of the deformed shape


Figure 3 shows the numerical and experimental results of the tension experiment using different assumptions for the initial shear modulus of the membrane and assuming an inviscid fluid. The dots and error bars show the range of the experimental results.



Figure 3 Results when viscosity of the cytoplasm is ignored; the experimental results
are shown by mean values and error bars


Figure 4 shows a comparison of the same experimental results with the ADINA FSI results when the cytoplasm is modeled as a viscous fluid. The results show that including the effect of viscosity improves the correlation of the numerical results with the experimental data (see transverse diameter results).


Figure 4 Results when viscosity of the cytoplasm is included; the experimental results
are shown by mean values and error bars


The modeling features available in ADINA for fully coupled fluid-structure systems where the structure can include general nonlinearities (geometric, material and contact), and the fluid can be a general fluid (incompressible or compressible Navier-Stokes fluid) — all in one program — are instrumental in many such practical applications.

For more information, please visit our page on Fluid-structure Interaction Capabilities.

Reference

  • C.Y. Chee, H.P. Lee, C. Lu, "Using 3D fluid-structure interaction model to analyse the biomechanical properties of erythrocyte", Physics Letters A, 372:1357-1362, 2008


Keywords:
Fluid structure interaction, FSI, red blood cell, erythrocyte, cytoplasm, hyperelastic, viscoelastic, large deformation, biomechanics, Navier-Stokes



Courtesy of C.Y. Chee (Ning Research), H.P. Lee (National University of Singapore), C. Lu (King Abdullah University of Science and Technology)