Quasi-Steady Flow Dynamics Study of Human Aortic Valve with Numerical Techniques

Abstract

Human aortic valve is made of thin collagen type tissue. The three leaflets open and close under fluid forces exerted upon them. To simulate the hemodynamic characteristics of the blood flow, ANSYS CFX10.0 software was utilized to analyze the three-dimensional Reynolds-averaged Navier-Stokes equations. With a quasi-steady analysis model, we predict values of the blood velocity and the wall shear stress both over the valve leaflets and the endothelial lining. In addition, investigation on fluid dynamic of a heart valve supposed suffering prolapsed disease has been also conducted, and compared with normal valve. Analysis results highlight that leaflet opening situation and valve geometry affect the shear stress distribution and vortex flow regime. Maximum shear stress takes place near the center of leaflet trailing edge at the very beginning of systolic phase with value of 7.093N/m 2 . At peak systole, the maximum wall shear stress distributes near the aortic root where jet impingement takes place. Current study also demonstrated the interactive impact between low and high wall shear stress on relation to heart valve disease.

Numerical Investigation of the Effects of Prosthetic Aortic Valve Design on Aortic Hemodynamic Characteristics

“…However, the extremely computation-intensive nature of the FSI method has constrained its application in dealing with large-scale models, which would take weeks to months to solve [62][63][64]. Compared with FSI simulation, the steady-state CFD simulation is advanced in providing a fast prediction of non-temporal flow characteristics with ease and has been widely used in the studies of valvular and aortic hemodynamics [65][66][67][68][69][70][71][72]. Despite the fact that the blood flow in the vascular system was pulsatile under physiological conditions, several numerical [73,74] and in vitro [75][76][77] studies have suggested that steady-state simulation can predict the non-temporal related flow characteristics at the corresponding point of the pulsatile flow profile.…”