In this study, numerical simulation was carried out to investigate the dynamic response of a systemic flow test rig that is widely used for in vitro study of prosthesis in the cardiovascular system. In the system the physiological impedance of systemic circulation was modeled as a resistance-capacitance-resistance type. The system analysis was directly based on differential equations describing the system dynamics, and numerically solved using the fourth-order Runge-Kutta method. Results showed that pressure in the systemic circulation test rig could be successfully simulated with the developed model. From the numerical experiment, it was found that the maximum stroke of the driving mechanism, the flow coefficients and opening of the control valves, and the initial volume of air in the compliance strongly affect the dynamic performance of the test rig. The numerical method developed is a useful tool in the design and optimization of the system configuration.
Systemic flow test rigs are widely used in the in vitro study of cardiovascular prostheses in early stage design and trials. A well designed systemic flow test rig is capable of reproducing the physiological impedance of systemic circulation with satisfactory accuracy, and this greatly assists the experimental study of prostheses in the cardiovascular system. Hence, good design and a well-constructed systemic flow test rig have drawn much attention from researchers in this field.
In the past, various pulsatile flow test rigs have been developed. 1-6 At the same time, several mathematical models have been proposed to describe the systemic circulation for different research purposes. 6-16 However, in the open literature, there has been limited information on the dynamic performance study of systemic flow test rigs with numerical methods. Numerical simulation offers researchers a useful and effective tool for designing suitable experimental configurations and also to optimize parameters for the system components. As a result, system performance can be improved greatly and the design process can be accelerated. In this study, numerical simulation was carried out to design and optimize the construction of a systemic flow test rig for heart valve experiments.