Structure of the secondary flow in the bifurcation of a blood vessel: patient-specific modeling and clinical Doppler measurements

The Hydrodynamics of a Swirling Blood Flow in the Left Heart and Aorta

“…This phenomenon was confirmed experimentally by measuring the drag in a flow past surfaces with dimples. It was shown that the swirling jets generated in the dimples and then integrated into the main flow significantly and reliably reduce hydrodynamic drag [ 13 ].…”

“…Hence, the medium is supplied into the jet only at its end rather than at its lateral boundary. This fact was proved experimentally by visualization of swirling jets in dimples [ 13 ].…”

“…These conditions imply that this boundary layer has a structure different from that for the Prandtl shear boundary layer. The experiments involving flowing past dimples made it possible to visualize the 3D vortex boundary layer in the jet base [ 13 ]. However, the challenges related to studying the boundary layer do not allow one to draw any definitive conclusions about its structure.…”

“…As its radius monotonically decreases, the jet is accelerated in the entire range of its existence. There is almost no transverse exchange with the ambient environment as demonstrated experimentally by a visualization of the swirling jets generated in the dimples [ 13 ].…”

“…These attempts have been made only in a few studies, but they actually incorporated only the general reasoning that as a flow swirl is a physiological norm, it is favorable for blood circulation [ 12 ]. Thus, a flow swirl was viewed as a result of pathological changes in the aortic wall caused by stenosis or atherogenesis [ 13 ]. In a long series of studies, the vortical structures emerging in the left ventricular cavity were viewed as a result of the separation of a jet filling the cavity at the edge of the mitral valve leaflet [ 14 , 15 ].…”