Abstract: The Guldner Frogger is a saline-filled rubber sac device used in the transformation of skeletal muscle for cardiac assist. The principal advantage of the device is that it offers a compliant rather than a resistive load against which the stimulated muscle contracts, which is reported to result in less muscle mass loss and superior final contractile characteristics. We are testing a locally developed version of the Frogger in live sheep, and using numerical modelling in the design of our device and its connection as a possible power source to an Australian ventricular assist device (VAD), called the Spiral Vortex. For overall consideration of pressure-volume-power relationships, a quasi-static lumped-parameter model involving simultaneous solution of equations describing the rubber stresses, the geometric constraints etc., has been found useful. The distributed pressure and velocity of this fluid was found from finite-volume solution of the Navier-Stokes equations, using commercial software.

Resume: A/Prof. Bertram originally graduated in Engineering Science and has had a long career in the mechanics of unsteady flows in the context of biofluid dynamics. He is a member of the World Council for Biomechanics, a Fellow of the Institution of Engineers Australia, and a member of the editorial board of Medical & Biological Engineering & Computing. He has published over 50 refereed journal articles, in the areas of measurement instrumentation, pulse wave propagation, flow in collapsed tubes, nonlinear dynamics, crossflow microfiltration and cardiac assist.
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