Dynamic simulation model for a vibrating fluid density sensor

A dynamic simulation model for a vibrating fluid density sensor is presented. The model includes electrostatic excitation, two torsional and two bending vibration modes of the double-loop structure and gas film damping. The damping model is based on the solution of the linearized Reynolds equation for rectangular surfaces. The model is constructed of lumped electrical equivalent circuit blocks and it can be simulated with a circuit analysis program in the frequency and time domains. Simulated and measured Q-factors and frequency responses at atmospheric pressures are in good agreement.

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