Nonlinear pressure-flow relationships for passive microfluidic valves.
An analytical solution is presented for the nonlinear pressure-flow relationship of deformable passive valves, which are formed by bonding a deformable film over etched channels separated by a weir. A fluidic pathway connecting the channels is opened when the upstream pressure creates a tunnel along a predefined narrow strip where the film is not bonded to the weir. When the width of the strip is comparable to the inlet channel width, the predicted closed-form pressure-flow rate relationship is in excellent agreement with experiments, which determine pressures by measuring film deflections for prescribed flow rates. The validated closed-form models involve no fitting parameters, and provide the foundation to design passive diodes with specific nonlinear pressure-flow characteristics.
Seker
Erkin
E
Center for Microsystems for the Life Sciences, University of Virginia, Charlottesville, VA 22902, USA.
Leslie
Daniel C
DC
Haj-Hariri
Hossein
H
Landers
James P
JP
Utz
Marcel
M
Begley
Matthew R
MR