Cheng-Chung Yang and Jr-Ming Miao and Fuh-Lin Lih and Tsung-Lung Liu and Ming-Hui Ho
The Performance Analysis of Valveless Micropump with Contoured NozzleDiffuser
508 - 513
2011
5
2
International Journal of Mechanical and Mechatronics Engineering
https://publications.waset.org/pdf/7194
https://publications.waset.org/vol/50
World Academy of Science, Engineering and Technology
The operation performance of a valveless micropump
is strongly dependent on the shape of connected nozzlediffuser and
Reynolds number. The aims of present work are to compare the
performance curves of micropump with the original straight
nozzlediffuser and contoured nozzlediffuser under different back
pressure conditions. The tested valveless micropumps are assembled
of five pieces of patterned PMMA plates with hotembracing
technique. The structures of central chamber, the inletoutlet
reservoirs and the connected nozzlediffuser are fabricated with laser
cutting machine. The micropump is actuated with circulartype PZT
film embraced on the bottom of central chamber. The deformation of
PZT membrane with various input voltages is measured with a
displacement laser probe. A simple testing facility is also constructed
to evaluate the performance curves for comparison.
In order to observe the evaluation of low Reynolds number
multiple vortex flow patterns within the micropump during suction
and pumping modes, the unsteady, incompressible laminar
threedimensional Reynoldsaveraged NavierStokes equations are
solved. The working fluid is DI water with constant thermophysical
properties. The oscillating behavior of PZT film is modeled with the
moving boundary wall in way of UDF program. With the dynamic
mesh method, the instants pressure and velocity fields are obtained
and discussed.Results indicated that the volume flow rate is not
monotony increased with the oscillating frequency of PZT film,
regardless of the shapes of nozzlediffuser. The present micropump
can generate the maximum volume flow rate of 13.53 mlmin when
the operation frequency is 64Hz and the input voltage is 140 volts.
The micropump with contoured nozzlediffuser can provide 7mlmin
flow rate even when the back pressure is up to 400 mmH2O. CFD
results revealed that the flow central chamber was occupied with
multiple pairs of counterrotating vortices during suction and
pumping modes. The net volume flow rate over a complete
oscillating periodic of PZT
Open Science Index 50, 2011