Fluidic operational amplifier for mock circulatory systems

For the development of cardiovascular devices and the study of the dynamics of blood flow through the cardiovascular system, hardware fluidic models are commonly used to minimize animal experiments and clinical trials. These systems, called "mock circulatory systems", are also critical for the development of ventricular assist devices. The passive and active elements in these systems are frequently "hard-plumbed" and are difficult to modify in experimental studies. Therefore, we propose a concept of novel fluidic operational amplifier comprised of a high-gain feedback-controlled gear pump. With pressure being the analog of voltage, design with the fluidic op-amp is analogous to electrical op-amp circuit design. Initial computer and hardware simulation results demonstrate that the device may be programmed for use in mock circulatory systems to emulate the function of the energy sources (the ventricles) or passive networks (hemodynamic loads).