No abstract

A Newtonian fluid is used in a simplified experimental hydraulic model of a cardiovascular system (CVS) to study pulsatile flow in arterial geometric models with different stages of stenosis (restriction rates) and understand the progression of stenosis and how the fluid flow properties in stenosed sections of arteries behave. In this study, 16mm long cylindrical stenosis models (orifices) with different restriction rates were pressed into the middle section of a 570 mm long arterial geometric model (polyethylene tube) one at a time. The arterial geometric models were connected to a solenoid or reciprocating pump (DC Voltage) capable of generating pulsatile flow at different pumping frequencies. The effects of pulsatile flow properties (pressure pulse, flow rate, etc) on acoustic emission (AE) signal levels using sensors for the detection of elastic waves in the arterial models for different restriction rates of stenoitic geometric models (orifices) at different pumping frequencies have been investigated. The results from this research show that there is a strong correlation between the flow properties of the Newtonian fluid in the arterial geometric models and the level of the flow induced AE signal indicators such as the waveforms, elastic energy, number of events, etc. Thus, as AE techniques can be used to predict flow characteristics in a given geometric model to assess the restriction level of a flow passage, the same principle could be applied in the detection of severe atherosclerosis or stenosis in large arteries — human external carotid arteries.