Capacitive micromechanical ultrasonic transducers(CMUTs)have been widely studied because they can be used as substitutes for piezoelectric ultrasonic transducers in imaging applications.However,it is unclear whether a...Capacitive micromechanical ultrasonic transducers(CMUTs)have been widely studied because they can be used as substitutes for piezoelectric ultrasonic transducers in imaging applications.However,it is unclear whether and how CMUTs can be developed for sensors incorporating other functions.For instance,researchers have proposed the use of CMUTs for pressure sensing,but fundamental and practical application issues remain unsolved.This study explored ways in which a pressure sensor can be properly developed based on a CMUT prototype using a simulation approach.A three-dimensional finite element model of CMUTs was designed using the COMSOL Multiphysics software by combining the working principle of CMUTs with pressure sensing characteristics in which the resonance frequency of the CMUT cell shifts accordingly when it is subjected to an external pressure.Simultaneously,when subjected to pressure,the CMUT membrane deforms,thus the pressure can be reflected by the change in the capacitance.展开更多
In order to design the inner and outer ring capacitance sensor used in measuring the correlation velocity of two phase flow and optimize its structure,the sensitivity characteristics of inner and outer ring capacitanc...In order to design the inner and outer ring capacitance sensor used in measuring the correlation velocity of two phase flow and optimize its structure,the sensitivity characteristics of inner and outer ring capacitance sensor were analyzed by using finite element simulation.The simulation experiment was planned by using orthogonal experimental design.From the simulation result,the major factors influencing the sensitivity characteristics(relative sensitivity and uniformity error) were obtained.The degree and tendency of influence of each factor on the sensitivity characteristics were given.The structural parameters of the sensor were determined.The analysis provided the theoretical basis for the inner and outer ring capacitance sensor.展开更多
文摘Capacitive micromechanical ultrasonic transducers(CMUTs)have been widely studied because they can be used as substitutes for piezoelectric ultrasonic transducers in imaging applications.However,it is unclear whether and how CMUTs can be developed for sensors incorporating other functions.For instance,researchers have proposed the use of CMUTs for pressure sensing,but fundamental and practical application issues remain unsolved.This study explored ways in which a pressure sensor can be properly developed based on a CMUT prototype using a simulation approach.A three-dimensional finite element model of CMUTs was designed using the COMSOL Multiphysics software by combining the working principle of CMUTs with pressure sensing characteristics in which the resonance frequency of the CMUT cell shifts accordingly when it is subjected to an external pressure.Simultaneously,when subjected to pressure,the CMUT membrane deforms,thus the pressure can be reflected by the change in the capacitance.
文摘In order to design the inner and outer ring capacitance sensor used in measuring the correlation velocity of two phase flow and optimize its structure,the sensitivity characteristics of inner and outer ring capacitance sensor were analyzed by using finite element simulation.The simulation experiment was planned by using orthogonal experimental design.From the simulation result,the major factors influencing the sensitivity characteristics(relative sensitivity and uniformity error) were obtained.The degree and tendency of influence of each factor on the sensitivity characteristics were given.The structural parameters of the sensor were determined.The analysis provided the theoretical basis for the inner and outer ring capacitance sensor.
