Denis,

I have published quite a bit on the subject.  See:

http://www.aquarianmicro.com/papers.html

Look in particular at journal papers J13, J14 and J15 under the link.
Also look at proceedings papers P46 and P48.

There are other papers relating to application of microvalves to flow
and pressure control; and, to the reliability of microvalves and
microflow systems based on microvalves.

You can email me if you want a copy of the papers; or, go through the
appropriate society links given, and purchase directly.

If you would, please email me the sources you have been searching for
papers on microvalve flow.

Generally speaking, microvalve design has three components:  the
actuator, which links actuation energy input to mechanical change in a
membrane or variable orifice; the mechanical behavior of the membrane or
variable orifice; and, the flow which results from the geometry which
results from the combination of the actuator and membrane/variable
orifice mechanics, and which also results from the boundary conditions
of pressure, temperature, and interaction between the fluid and valve
materials.

In a 'good' valve design, the ratio between ON flow resistance and OFF
flow resistance is many orders of magnitude (for compressible gases).
Some published models of compressible gas flow focus on flow regimes
where the flow is always highly restricted, whether the valve is ON or
OFF.  In my opinion (based on my previous experience with the analogous
electron 'valves' called MOSFETs), such models aren't very useful,
because the valves they model have a very high pressure drop, and so
have very limited application.

Also in a 'good' valve design, the three design components can be (and
in my opinion should be) completely separable.

In the pneumatic and thermopneumatic designs I have done, and also in
some more recent but unpublished piezoelectric designs, I use an
orifice-type valve seat, with flow modulated by a membrane moving
against the seat.  The membrane mechanics are one part of the design.
The compressible gas or incompressible liquid flow model (given in the
above references) is a second component of the design.  The actuation of
the membrane is the third component of the design.

Hope that helps.

Best regards, Al

---
Albert K. Henning, PhD
Director of MEMS Technology
NanoInk, Inc.
215 E. Hacienda Avenue
Campbell, CA  95008
408-379-9069  ext 101
[email protected]

-----Original Message-----
From: Denis Petrov [mailto:[email protected]]
Sent: Monday, June 23, 2008 5:39 AM
To: [email protected]
Subject: [mems-talk] A method to design and calculate the parameters of
amechanical normally-closed microvalve with electrostatic actuation

Hello,

I am looking for a good literature (or any other) source on the method
for
the calculation of microvalve parameters (geometry, flow rates etc.).
I have been searching for a long time, but what I see is mostly
theoretical
descriptions of main microfluidic interelations.
I need a method, an approach.

Does anybody know something on the topic? Or possibly has some
expirience
with such (or similar) a design task?