A Robust Low-Cost PDMS Peristaltic Micropump With Magnetic Drive

This paper presents lumped-parameter simulation of dynamic characteristics of peristaltic micropumps. The pump consists of three pumping cells connected in series, each of which is equipped with a compliant diaphragm that is electrostatically actuated in a peristaltic sequence to mobilize the fluid. Diaphragm motion in each pumping cell is first represented by an effective spring subjected to hydrodynamic and electrostatic forces. These cell representations are then used to construct a system-level model for the entire pump, which accounts for both cell-and pump-level interactions of fluid flow and diaphragm vibration. As the model is based on first principles, it can be evaluated directly from the device's geometry, material properties and operating parameters without using any experimentally identified parameters. Applied to an existing pump, the model correctly predicts trends observed in experiments. The model is then used to perform a systematic analysis of the impact of geometry, materials and pump loading on device performance, demonstrating its utility as an efficient tool for peristaltic micropump design.

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Dynamic simulation of a peristaltic micropump considering coupled fluid flow and structural motion

Lin¹,

Yang²,

Xie³

et al. 2006

“…These demands make microdiaphragm pumps with active valves the optimum candidate for this application. Although there have been several publications on micro-diaphragm pumps with active valves [6][7][8][9][10][11][12] we did not find any appropriate theory to predict the performance of such a micropump as a function of its geometry and actuation force. We have therefore developed a theory based on lumped-parameter modeling.…”

Section: Introductionmentioning

confidence: 74%

A generic analytical model for micro-diaphragm pumps with active valves

Goldschmidtböing

Doll

Heinrichs

et al. 2005

We present a fully analytical model for micro-diaphragm pumps with active valves, based on the peristaltic working principle. Our model is suited for very fast as well as for very slow actuation mechanisms. Therefore it can be applied to a variety of actuation principles, e.g. piezoelectric, pneumatic, thermo-pneumatic or pre-stressed shape memory actuation. We show that the dynamics of this kind of micropump can be fully described by a lumped element approach taking only the mechanical behaviour of the diaphragms and the viscous losses at the valves into account. The full flow versus frequency and backpressure characteristic is derived. Our model is capable of predicting the maximum achievable flow rate and the maximum sustainable backpressure of micro-diaphragm pumps with active valves. Different modes of operation, which are distinguished by the speed of the actuation mechanism, the pressure history inside the pump and the applied driving scheme, are identified. We show that micro-diaphragm pumps with active valves generally suffer from a linear dependence of the flow rate on the applied backpressure. This fact, which is already known from micropumps with passive valves, is remarkable, because it is in contradiction to the characteristics of macroscopic peristaltic pumps. A set of design rules for the dimensioning of the valves in dependence on the actuation force and the desired hydrodynamic characteristics (maximum flow rate and maximum sustainable backpressure) are derived. Our theoretical results are proven by experimental results of our piezoelectrically actuated micropump. A maximum flow rate of 1.4 ml min−1 and a maximum sustainable backpressure of 40 kPa were achieved.

“…The most common representative of dynamic pumps is an electroosmotic pump [6]. Elecroosmotic pumps have the advantage of high back-pressures and simple designs [7], but their performance mostly depends on fluid and surface properties [6,8].…”

Section: Introductionmentioning

confidence: 99%

Piezoelectric peristaltic micropump with a single actuator

Pečar¹,

Križaj²,

Vrtačnik³

et al. 2014

A high performance piezoelectric PDMS peristaltic micropump with a single actuator is presented that enables driving with less expensive and simpler single-phase controllers while maintaining all the superior properties of conventional peristaltic micropumps, such as robustness, simplicity and purity due to the absence of valves. A simple structural design is based on a centrally placed inlet port which leads directly into the center of the pumping chamber. During excitation the loosely attached glass membrane and elastomer (PDMS) deform in a controlled manner, which enables compression and expansion of the central inlet port and the outlet fluidic channel with a phase lag that is typical for operation of peristaltic pumps. For proper micropump operation, the volume of the circular pumping chamber area should be much larger than the volume around the secondary deformation extremum that appears in the area of the outlet fluidic channel. To experimentally validate the principle of operation and evaluate the repeatability of the fabrication process, four monoactuator peristaltic (MAP) micropump prototypes were fabricated and characterized. Fabricated prototypes featured high water / air flowrate performance (up to 0.24 ml min−1/up to 0.84 ml min−1), back-pressure performance (up to 360 mbar/up to 80 mbar) and suction pressure performance (down to −165 mbar/down to −140 mbar). Furthermore, bubble tolerance and self-priming capability have been proved, together with valve regime of operation that enables sealing of the fluidic path when appropriate dc voltage is applied.