Effect of Magnetic Fluids on the Efficiency of an Electromagnetic Actuator Prototype

Abstract

An electromagnetic actuator to substitute ventricular function presents some advantages compared with different energy converters. The drastic reduction of the moving parts leads to greater reliability and an accurate control system can be set up. Its major limitations concern weight, heat dissipation and, finally, the overall pump efficiency which is usually rather low. We investigated the possibility of using magnetic fluids in an electromagnetic actuator. Limitations intrinsic to the magnetic fluids prevent their being used as pumping elements but they can be useful to increase the pump efficiency by reducing losses in the magnetic circuit. A remarkable increase in pump efficiency was attained. It is necessary to point out that in designing the electromagnetic actuator the focus was on the pump efficiency with and without the magnetic fluids more than on its performance.

How to transform a fixed stroke alternating syringe ventricle into an adjustable elastance ventricle

“…For this reason, many mechanical simulators of the cardiovascular system varying in complexity and approach (syringe-like, elastic chamber inside a fluid-filled rigid box, etc.) have been developed and are currently used both for teaching and research [11][12][13][14][15][16][17][18][19][20][21][22] . Nevertheless, the paucity and cost of standardized cardiovascular commercial mocks (e.g., VivitroSuperPump, ViVitro Labs, Victoria, BC, Canada) have stimulated a continuous process of innovation and proposals aimed at overcoming the functional limitations of existing solutions.…”

“…In some cases, the ventricle is made of a chamber filled with liquid surrounded by air: the ventricular elastance can be adjusted by controlling the external air pressure and volume separately from the pumping function. To do this, motors and valves and an external electronic device must be added to the mock pumps to properly control these additional parts [16][17][18][19]21,22,40,41 . Moreover, the elastance may also be changed according to physiological values previously acquired from patients, and the Frank Starling mechanism simulated.…”