Modeling of Noise Generation by a Vascular Stenosis

Experimental Study of Noise Produced by Steady Flow Through a Simulated Vascular Stenosis

“…This spectrum was found in references [10,16] to have a maximum in this domain (see Figure 9), and the frequency of the maximum can be attributed to the characteristic frequency of the large turbulent eddies. Consequently, one can conclude that the power spectrum of the wall pressure in zone 1 should exhibit a low-frequency maximum in the range determined by the characteristic frequency f AF , namely…”

“…The silicone elastic pipe was chosen as a model of a larger blood vessel because it allows close matching of geometrical and physical parameters (see Table 1), and also because silicone and latex pipes are widely used as a mechanical analogue of blood vessels in both medical practice and in vitro studies [14,16]. Stenosis: The representation of a stenosis as a rigid-walled constriction is justi"ed by the fact that the wall of an arterial stenosis has high sti!ness compared with that of the vessel proximal and distal to the stenosis [3}7, 11}14].…”

“…where u A :0)45}0)6u is a convection velocity on the outer side of the shear layer [10,16,25,26]. Taking into account the arguments used for zone 1 one can conclude that the power spectrum of wall pressure in zone 3 should exhibit two peaks in the low-frequency ranges determinable by frequencies (10) and (11), namely…”

“…Abdallah and Hwang [10] and Borisyuk [16] found isolated peaks in the power spectrum of turbulent wall pressure behind a constriction and showed that their position in the spectrum depends on the axial distance downstream from the constriction. The frequencies of these peaks were attributed to the characteristic frequencies of large-scale turbulent eddies behind the constriction exit.…”

Computational analysis of high frequency fluid–structure interactions in constricted flow

“…This method makes use of the acoustic radiation due to the abnormal conditions in the blood flow and it is studied and applied by a number of researchers [7][8][9][10]. Nearly all of the authors stated that the reason of abnormal flow conditions in a stenosed flow is disturbed flow characteristics and the main source of the vascular noise field is found to be the turbulent pressure fluctuations in the blood vessel [3,8,9,11,12,7]. When passing over a stenotic lesion, the regular flow character of fluid changes due to the constriction.…”