Quantifying volume loss of a magnetically localized ferrofluid bolus in pulsatile pipe flow

Abstract

We report on experiments in a model blood vessel of miscible ferrofluid regions held in place by permanent magnets of different strengths and subject to pulsatile flow at various Womersely numbers of O(10). Using image analysis, we quantify the dependence of ferrofluid volume loss, or “wash away,” rate due to hydrodynamic processes, identifying two distinct regimes. Complementary PIV allows visualization of the flow fields that correlate with volume loss, suggesting that volume loss may be a complex combination of vortex shedding during the primary pulse and re-combination during quiescent phase.