Secondary Piezoresonance Transducer for Diagnostic Spirometer

The presented work is devoted to the development of a secondary measuring transducer for a portable spirometer based on the use of a piezoresonator with a gap. A 3D model of the Venturi flowmeter was created using SolidWorks CAD software, followed by static and dynamic studies. The simulation results made it possible to determine the radial displacement range of the measuring bands at maximum and minimum inlet flow rates. Families of control characteristics for a measuring transducer with inter-electrode gap modulation (MTIGM) using different combinations of measuring band thicknesses were constructed. It is found that by selecting optimum measuring band thicknesses it is possible to achieve the desired linearity of the control characteristics for a secondary measuring transducer.