Acoustically generated flows in microchannel flexural plate wave sensors: Effects of compressibility

Sayar E., Farouk B.

SENSORS AND ACTUATORS A-PHYSICAL, vol.171, no.2, pp.317-323, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 171 Issue: 2
  • Publication Date: 2011
  • Doi Number: 10.1016/j.sna.2011.08.018
  • Journal Name: SENSORS AND ACTUATORS A-PHYSICAL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.317-323
  • Keywords: Flexural plate wave (FPW), Acoustic streaming, Microchannel, Micropump, Acoustic waves, Fluid damping, Lamb wave
  • Istanbul Technical University Affiliated: No

Abstract

Acoustically generated flowfields in flexural plate wave sensors filled with a Newtonian liquid (water) are considered. A computational model based on compressible flow is developed for the sensor with a moving wall for pumping and mixing applications in microchannels. For the compressible flow formulation, an isothermal equation of state for water is employed. The velocity and pressure profiles for different parameters including flexural wall frequency, channel height, amplitude of the wave and wave length are investigated for four microchannel height/length geometries. It is found that the flowfield becomes pseudo-steady after sufficient number of flexural cycles. Both instantaneous and time averaged results show that an evanescent wave is generated in the microchannel. The predicted flows generated by the FPWs are compared with results available in the literature. The proposed device can be exploited to integrate micropumps with complex microfluidic chips improving the portability of micro-total-analysis systems. (C) 2011 Elsevier B.V. All rights reserved.