Pumps for Human Blood Pressure Simulation - Microsurgery: Advances, Simulations, and Applications - page 206

cycle. Several kinds of pumps were compared for this purpose:
Peristaltic pumps introduce undesired vibrations on the low at
low low rates. Diaphragm pumps not only introduce noise on the
low but also are too loud to be used for this kind simulation. Gear
pumps and turbine pumps have big inertia to control precisely the
waveform.

Lobes Variable Accumulator Variable Accumulator

Pump and
Controller

Inflow

Outflow

Lobe Pump
Reciprocation

Piston Pump
Cylinder Wall

Figure 6.1 Schematic of the hybrid pump for human blood pressure
simulation.

In this chapter, we will present two pumps for human blood
pressure simulation and vasculature models enabling luid circulation
and photoelastic stress analysis. These vasculature models have a
urethane elastomer layer shielded with silicone layers to prevent
plastic deformation and to isolate urethane from the environment
and luid circulation. The irst pump proposed is a hybrid pump that
combines the features of lobe and piston pumps; the piston provides
a carrier waveform at the heart beat frequency, and the lobe pump
provides the minimum pressure and ine waveform tuning. It uses
pressure and frequency feedback control to reconstruct a pressure
waveform deined by polynomial functions. The second system uses
a single magnetic drive pump with pressure feedback control for
maximum and minimum pressures, the reproduced waveforms a
result of open loop control of predeined functions and frequencies.
A schematic of the hybrid pump is shown in Fig. 6.1 and the pressure
variation in the outlow for the piston pump is shown in Fig. 6.2.