【摘要】 为满足超声传感器非接触、非浸入、完全无损及易于集成等要求,提出了一种电容式微机械超声换能器(CMUT)的简单质量-弹簧理论计算模型,结合薄板振动理论,设计了传感器特征参数、谐振频率和塌陷电压等参数,并对其进行仿真验证。结果表明:由该模型得到的理论计算结果和软件仿真结果,经对比其误差在4%之内,能很好满足设计要求,并验证了简单质量-弹簧模型的可行性;在标准大气压和外加塌陷电压作用下,薄板挠度约为空腔高度减去薄板挠度(只在大气作用下的薄板挠度)时的1/3;设计的一阶谐振频率为530 kHz的低频传感器可用于空耦超声检测。更多还原

【Abstract】 In order to meet the requirement of non-contact, non-immersion, and complete non-destructive application of probe sensor to the nondestructive testing of composite materials, this paper presents a calculation model of simple mass-spring based on the capacitive micro-electromechanical ultrasonic transducer(CMUT), and verifies the designed capacitive ultrasonic sensor through COMSOL simulation software. Combined with the vibration theory of thin plate, the characteristic parameter of the sensor, resonance frequency and collapse voltage are designed and simulated. The results show that the theoretical calculation results and simulation results obtained by the model have an error within 4%. which can well meet the design requirement and verify the feasibility of the simple model. Under the action of standard atmospheric pressure and applied collapse voltage, the deflection of the thin plate is about 1/3 of the height of the cavity minus the deflection of the thin plate(the deflection of the thin plate only under the action of the atmosphere). The designed CMUT with first-order resonant frequency of 530 k Hz can meet the design requirements of air-coupled nondestructive testing sensors.更多还原