A constant flow-rate microvalve actuator based on silicon and micromachining technology

Computer modeling and prototype testing of a nearly constant flow-rate microvalve which requires no power consumption to maintain the flow rate has been presented. The parameters of the valve have been obtained by mathematical models with correction factors from the experimental trials. These parameters allow for general design guidelines for a rectangular, thin diaphragm microvalve. To have the experimental data agree with the theoretical model, using the method of least squares, for the prototype rectangular silicon valve described the correction coefficient is 0.45-0.55 for a diaphragm aspect ratio for L/W=2 and 0.8-0.9 for an aspect ratio of L/W=4. The correction factor accounts for the simplified diaphragm deflection equations, incorrect estimated elastic modulus of the diaphragm, and variation in the diaphragm material thickness.<>