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For the purposes of analyzing the possible impact of external factors on the performance and reliability of a left ventricular assist device (LVAD), a pulmonary simulator (PS) would be critical for in vitro use within a mock circulatory loop (MCL). In order to accurately reproduce the conditions within the pulmonary system, a PS should not only account for the capacity of the pulmonary system to supply flow at given pressures, but also consider the systemic outflow dynamics. This would allow for an accurate pressure and flow rate return feed back into the left ventricular portion of the MCL, i.e. the initial conditions of the left heart. Utilizing Windkessel modeling techniques, a computational model was developed using Simulink® Simscape™ that generates the left atrial pressure (LAP) waveform for given aortic conditions, systemic variables, and pulmonary factors. The adaptability of this model provides the ability to reproduce a wide range of circulatory conditions without the limitations of a dedicated hardware platform. Following a verification and validation (V&V) model, a PID-controlled closed-loop hydraulic system was developed utilizing Simulink® Simscape™. Once this simulation is completed, testing of the PS will be conducted on an MCL. Simulink® Simscape™ was used (1) to control the in silico system during verification studies of the PS and (2) to simulate pulmonary performance for validation of the control architecture used. Verification of the PS performance and validation of the control architecture support this modeling method as an effective means of reproducing pulmonary pressure and systemic outflow.

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