Laboratory of Microsensor Structures and Electronics
Faculty of Electrical Engineering
Physics & device modelling
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NUMERICAL SIMULATIONS OF NEW ELASTOMERIC MICROPUMP PROTHOTYPES
Micropumps are an essential part of microfluidic devices such as "labs-on-chip" micro TAS (total analysis systems). Elastomeric micropumps in particular have become increasingly employed in biomedical devices due to their capacity for regulated closure regulated by the deformation of piezoelectricaly actuated membranes | ||||||||
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We developed a fully coupled 3D electro-fluid-solid mechanics simulation model in COMSOL, including fluid inertial effects, hyperelastic model for PDMS and non-slip boundary condition in fluid-wall interface. Numerical simulation enabled virtual prototyping of the proposed device, enabling detailed insight into device operation, at various frequencies, revealing basic pumping effects, role of the excitation signal amplitude and backpressure as well as optimization of several design parameters (see the below images). | ||||||||
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Based on numerical simualtions, we proposed first strip type MT pump which is particular suitable for applications in case of several parallel microchannels, enabling individual channel pumping, at minimal chip surface consumption.
3D fully coupled model enabled investigation of structural deformations, pressure distribution and fluid velocity (vectors) for selected time frames (see the above image on the right hand side). Numerical simulation of membrane deflection in a middle cross-section along the channel for three frequencies is presented below | ||||||||
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We analysed micropump flow-rate response on various waveforms as depictured below: | ||||||||
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DESIGN AND OPTIMISATION OF PIEZORESISTIVE FLOW-RATE SENSOR
Silicon cantilever with integrated diffused piezoresistive resistor is installed in the pipe. Stress as well as resistance of piezoresistive layer was simulated for selected medium flow-rate values (see below images).
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University of Ljubljana