Effect of turbulent models on left ventricle diastolic flow patterns simulation

Comput Methods Biomech Biomed Engin. 2019 Nov;22(15):1229-1238. doi: 10.1080/10255842.2019.1655642. Epub 2019 Aug 22.

Abstract

Vortex structures, as one of the most important features of cardiac flow, have a crucial impact on the left ventricle function and pathological conditions. These swirling flows are closely related to the presence of turbulence in left ventricle which is investigated in the current study. Using an extended model of the left heart, including a fluid-structure interaction (FSI) model of the mitral valve with a realistic geometry, the effect of using two numerical turbulent models, k-ε and Spalart-Allmaras (SA), on diastolic flow patterns is studied and compared with results from laminar flow model. As a result of the higher dissipation rate in turbulent models (k-ε and SA), vortices are larger and stronger in the laminar flow model. Comparing E/A ratio in the three models (Laminar, k-ε, and SA) with experimental data from healthy subjects, it is concluded that the results from k-ε model are more accurate.

Keywords: Left heart hemodynamics; Spalart-Allmaras (SA) model; fluid-structure interaction; k-ε; mitral valve vortex ring; model; turbulent flow.

MeSH terms

  • Blood Flow Velocity
  • Computer Simulation*
  • Coronary Circulation / physiology*
  • Humans
  • Mitral Valve / physiology
  • Models, Cardiovascular*
  • Numerical Analysis, Computer-Assisted
  • Pressure
  • Stress, Mechanical
  • Ventricular Function / physiology*