The Performance Analysis of Valveless Micropump with Contoured Nozzle/Diffuser
The operation performance of a valveless micro-pump
is strongly dependent on the shape of connected nozzle/diffuser and
Reynolds number. The aims of present work are to compare the
performance curves of micropump with the original straight
nozzle/diffuser and contoured nozzle/diffuser under different back
pressure conditions. The tested valveless micropumps are assembled
of five pieces of patterned PMMA plates with hot-embracing
technique. The structures of central chamber, the inlet/outlet
reservoirs and the connected nozzle/diffuser are fabricated with laser
cutting machine. The micropump is actuated with circular-type 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
three-dimensional Reynolds-averaged Navier-Stokes equations are
solved. The working fluid is DI water with constant thermo-physical
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 nozzle/diffuser. The present micropump
can generate the maximum volume flow rate of 13.53 ml/min when
the operation frequency is 64Hz and the input voltage is 140 volts.
The micropump with contoured nozzle/diffuser can provide 7ml/min
flow rate even when the back pressure is up to 400 mm-H2O. CFD
results revealed that the flow central chamber was occupied with
multiple pairs of counter-rotating vortices during suction and
pumping modes. The net volume flow rate over a complete
oscillating periodic of PZT
[1] H. T. G. Van Lintel, "A piezoelectric micropump based on
micromachining of silicon," Sensors and Actuators: A-Physical, vol.15,
pp. 153-167, 1988.
[2] A. Olsson, G. Stemme, and E. Stemme, "A valve-less nozzle/diffuser
based fluid pump," Sensors and Actuators: A-Physical, vol.39,
pp.159-167, 1993.
[3] A. Olsson, G. Stemme and E. Stemme, "Micromachined flat-walled
valveless diffuser pumps," J. of Micro-electro-mechanical Systems,
vol.6, pp. 126-135, 1999.
[4] A. Olsson, G. Stemme and E. Stemme, "Numerical and experimental
studies of flat-walled diffuser elements for valve-less micropumps,"
Sensors and Actuators: A-Physical, vol. 46, pp. 165-175, 2000.
[5] H.C., Chen H.C., "The study on the nozzle/diffuserof a micropump,"
M.S. Thesis, Hu-Cha University, 2004.
[6] V. Singhal and S. V. Garimella, "A novel valveless micropump with
electrohydrodynamic enhancement for high heat flux cooling," IEEE
Trans. on Advanced Packaging, vol. 28, pp. 216-230, 2005.
[7] V. Singhal, S. V. Garimella, and J. Y. Murthy, "Low Reynolds
number flow through nozzle-diffuser elements in valveless
micropumps," Sensors and Actuators: A-Physical, vol. 113, pp.
226-235, 2004.
[1] H. T. G. Van Lintel, "A piezoelectric micropump based on
micromachining of silicon," Sensors and Actuators: A-Physical, vol.15,
pp. 153-167, 1988.
[2] A. Olsson, G. Stemme, and E. Stemme, "A valve-less nozzle/diffuser
based fluid pump," Sensors and Actuators: A-Physical, vol.39,
pp.159-167, 1993.
[3] A. Olsson, G. Stemme and E. Stemme, "Micromachined flat-walled
valveless diffuser pumps," J. of Micro-electro-mechanical Systems,
vol.6, pp. 126-135, 1999.
[4] A. Olsson, G. Stemme and E. Stemme, "Numerical and experimental
studies of flat-walled diffuser elements for valve-less micropumps,"
Sensors and Actuators: A-Physical, vol. 46, pp. 165-175, 2000.
[5] H.C., Chen H.C., "The study on the nozzle/diffuserof a micropump,"
M.S. Thesis, Hu-Cha University, 2004.
[6] V. Singhal and S. V. Garimella, "A novel valveless micropump with
electrohydrodynamic enhancement for high heat flux cooling," IEEE
Trans. on Advanced Packaging, vol. 28, pp. 216-230, 2005.
[7] V. Singhal, S. V. Garimella, and J. Y. Murthy, "Low Reynolds
number flow through nozzle-diffuser elements in valveless
micropumps," Sensors and Actuators: A-Physical, vol. 113, pp.
226-235, 2004.
@article{"International Journal of Mechanical, Industrial and Aerospace Sciences:56271", author = "Cheng-Chung Yang and Jr-Ming Miao and Fuh-Lin Lih and Tsung-Lung Liu and Ming-Hui Ho", title = "The Performance Analysis of Valveless Micropump with Contoured Nozzle/Diffuser", abstract = "The operation performance of a valveless micro-pump
is strongly dependent on the shape of connected nozzle/diffuser and
Reynolds number. The aims of present work are to compare the
performance curves of micropump with the original straight
nozzle/diffuser and contoured nozzle/diffuser under different back
pressure conditions. The tested valveless micropumps are assembled
of five pieces of patterned PMMA plates with hot-embracing
technique. The structures of central chamber, the inlet/outlet
reservoirs and the connected nozzle/diffuser are fabricated with laser
cutting machine. The micropump is actuated with circular-type 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
three-dimensional Reynolds-averaged Navier-Stokes equations are
solved. The working fluid is DI water with constant thermo-physical
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 nozzle/diffuser. The present micropump
can generate the maximum volume flow rate of 13.53 ml/min when
the operation frequency is 64Hz and the input voltage is 140 volts.
The micropump with contoured nozzle/diffuser can provide 7ml/min
flow rate even when the back pressure is up to 400 mm-H2O. CFD
results revealed that the flow central chamber was occupied with
multiple pairs of counter-rotating vortices during suction and
pumping modes. The net volume flow rate over a complete
oscillating periodic of PZT", keywords = "valveless micropump、PZT diagraph、contoured
nozzle/diffuser、vortex flow.", volume = "5", number = "2", pages = "362-6", }