Smoothing Oscillatory Peristaltic Pump Flow with Bioinspired Passive Components

Abstract

Pulsating flows are common in many industrial, scientific, and natural fluidic systems. However, because the oscillatory flow component disturbs, e.g., optical measurements, deposition, or industrial processes, it is rarely desired. Moreover, in physiological conditions, pulsation control is desired. We explore the effect of using a plant-inspired nonlinear resistor to smooth the output of a peristaltic pump. Incorporating a 3D printed millifluidic biomimetic device reduces the oscillation amplitudes by 3 orders of magnitude, from 100% to 0.1% of the output flow rate. This represents a tenfold improvement relative to a purely linear resistive-capacitive approach. The observed flow kinetics compare well to a predictive model of peristaltic transport, allowing the further development of optimized fluid-handling systems driven by pulsatile flow. Applications to particle tracking and jetting are considered.

Tailoring 3D printed cellulose acetate properties produced via direct ink writing: Densification through over‐extrusion and evaporation rate control

“… There will be multiple back‐flow pulses equal to the number of rollers for each complete revolution of the rotor, and the frequency is provided by the number of rollers multiplied by the rotor angular velocity, given by Although we did not record any major deviation from the nominal dimensions of our samples, the pulsating flow rate is a limitation to keep in mind when printing components (especially small ones) requiring extreme dimensional accuracy. For a more detailed analysis of the performance of peristaltic pumps, we address the reader to some recent articles 29–32 …”

Elastohydrodynamic interactions in soft hydraulic knots

“…2021; Biviano et al. 2022). Improving the description of the deformation in the knot junctions, as well as addressing the non-uniform junction pressure gradient, may result in non-monotonic relationships.…”

“…Our model predicts a monotonic flow-pressure relationship for all configurations. Members of our team have previously explored soft channel devices with non-conforming channel cross-sections that also exhibit non-monotonic flow-pressure relationships (Park et al 2021;Biviano et al 2022). Improving the description of the deformation in the knot junctions, as well as addressing the non-uniform junction pressure gradient, may result in non-monotonic relationships.…”

“…Introducing a compliant vessel between the pump and device can attenuate some, but not all, ripples in the peristaltic flow (Kang & Yang 2012;Kang et al 2014). Further improvements can be made by including a compliant vessel and a passive nonlinear resistance that only permits one specific flow rate within a range of pressure, akin to the flow limitation exhibited by our hydraulic knots (Doh & Cho 2009;Zhang et al 2015;Biviano et al 2022). However, the introduced nonlinear resistances need to be carefully tuned such that the flow rate limitation level matches the application specifications.…”

“…For the [12] and [1342] knots it is not unlikely that the smoothing can be improved in response to, e.g. increasing the pumping frequency, as demonstrated by Biviano et al (2022) using similar nonlinear hydraulic resistances.…”